8 ms·

BMW F Series Gear Selector, Part One: Failures

140 points by zdw 4y ago

yuppie_scum 4y ago
I read like halfway through the article and felt like this hardware was, in classic German car fashion, very over-engineered for the relatively simple purpose of sending one of 5-6 signals to a transmission controller.
- KerrAvon 4y ago
  On one hand, you really do not want this part to fail. On the other, why is it this complicated in the first place? These overcomplicated shift levers that you need to watch a video to understand seem to be an industry fad — one of them in a Chrysler product (IIRC) killed a Star Trek actor a few years ago.
  - amluto 4y ago
    Tactile feedback (like something that actually locks into a park position when it’s in park) is genuinely useful. Tesla uses a little lever with four possible momentary positions. There is no way to feel whether you have actually selected the correct mode. You’re choices are to either look at the instrument cluster and read the gear status or to actually try driving the car. This is made worse by the fact that, on level ground with creep off, park and drive behave identically unless someone presses the accelerator or tries pushing the car. On the flip side, I’ve driven a BMW with a really amazing 2D joystick with software controlled detents corresponding to buttons on the infotainment screen. I’m not convinced it’s a good idea, but the engineering is awesome.
    - doubled112 4y ago
      I don’t like a lot of the UI/UX decisions in modern cars. Every manual transmission I’ve ever driven has given an incredible amount of tactile feedback when you get it wrong. You know you’re parked because you’ve pulled a (relatively) big lever. A little knob or momentary buttons make me uncomfortable. I’d be waiting for feedback but never receiving it. Another example of waiting for something to happen, then nothing happens is start/stop engines. My foot goes down, nothing happens, I give more fuel, still nothing, engine starts and we’re really going. I’m sure I’d get used to it, but I don’t like it. Just do what you’re told, car.
      - lttlrck 4y ago
        start/stop isn't triggered by the accelerator. The engine starts immediately when the brake is released. For most drivers it is unnoticeable. I don't like it but that's because there is little intelligence deciding when it should stop in the first place, though you can kind of regulate it by being extremely light on the pedal.
      - vel0city 4y ago
        As someone else mentioned, start/stop isn't usually triggered by the gas pedal but by releasing the brake. You're probably pretty quick to go from the brake to the gas for your car's start/stop, practice getting off the brake a hair earlier than you do currently. You probably won't roll much since you've got a dead engine holding the car, so don't worry about needing to be quick. I've driven some cars with start/stop and while it was a bit of a different feel for it originally I managed to get the timing down pretty well to have the car do what I wanted. Start/stop isn't driven by a random number generator you can figure out when it'll kill it and how long it goes from getting off the brake to the time it starts. Then it's just like every other tool in the car.
  - elvis70 4y ago
    Yes, it was a 2015 Jeep Grand Cherokee https://www.nbcnews.com/business/autos/death-star-trek-actor-highlights-concerns-about-faulty-electronic-shifters-n595751 https://www.nbcnews.com/business/autos/death-star-trek-actor...
  - wil421 4y ago
    The shifter was a Bosch part IIRC and was very similar to Audi shifters. Since then if you open your door and depress the brake it will automatically go into park. They also changed the shifter in 2016. 2014/15 model Grand Cherokees have it and many people complained about it.
  - izacus 4y ago
    It truly is bizarre - I've driven a lot of cars lately and this exact BMW shifter took the cake of the most unintutitive and annoying to use by far. (And it's not even the most dumbass UX decision in that BMW by far.)
    - RedShift1 4y ago
      I don't get it. All these joystick gear selectors work the same. Push and hold a button and move it to the setting you want. What is unintuitive and annoying about this?
      - gonesilent 4y ago
        Chrysler's attempt at a reimagined shifter killed Star Trek's Chekov. Couldn't tell when it was in park...
        sgt 4y ago
        This type of technology has to work even when you have a "weak" moment of lapse in judgement. Everyone has those, at the very least a few in your adult lifetime.
      - izacus 4y ago
        Ah sorry, the 1 series I just drove also had an "unlock" button on the left side so you had to hold it in a rather unnatural way to get it to move around. And the separate "P" button is also something that kept throwing me off. In comparison, Mazda I drove had much much simpler approach - grab the stick, push it all the way forward for Park, push it all the way back for Drive. That's it. The "unlock" button was under the index finger so you just grabbed it naturally. (In general, Mazda felt much better thought out inside than VWs, BMWs and MBs I drove.)
    - t0mas88 4y ago
      Exact opposite experience for me, I can use this thing without looking and it does exactly what's expected. It also does manual shifting the right way around, pull to shift up, push to shift down. That's how every sequential racing gearbox works. But somehow a lot of non-sports brands do their manual control the wrong way around.
- deleted 4y ago
  [deleted]
jjtheblunt 4y ago
https://www.bmw.de/de/shop/ls/dp/physical-goods/12556 https://www.bmw.de/de/shop/ls/dp/physical-goods/12556 explains what GWS is...as mentioned in the article
- closewith 4y ago
  To save a click, GWS is Gangwahlschalter or gear selector switch.
  - dtgriscom 4y ago
    "Gear Which Switch"?
    - jjtheblunt 4y ago
      wa"hlen is to choose. which is welche. perhaps cognates
techwiz137 4y ago
It is very sad that a lot of older automatics needed actual mechanical linkages instead of entirely digital signals. It would've allowed some pretty custom gear selectors that would've enabled even more mods by freeing up space in the car interior.
- hotpotamus 4y ago
  There were push button automatics in the 50's. But for the life of me I've never seen the problem with a column shifter which was normal when I learned to drive a car in the late 90's.
  - tadfisher 4y ago
    The push buttons were also mechanically linked! At least Chrysler selectors such as the one used in the Plymouth Valiant, they actuated cables to open/close fluid paths in the transmission.
    - hotpotamus 4y ago
      Yeah, I'm aware that old auto transmissions had what - valve bodies? - analog computers to apply logic on when to shift; they'd have to have something. I just don't think the linkage was all that important a feature - mechanical or electronic seem to both be flexible enough to do the job. I mostly drive manuals, but the column shifter for autos seems the most utterly logical way to put transmission control right at your hands. It seems like putting it on top of where a transmission hump might go (but probably doesn't in a modern car with a transverse engine) is just pretending to be something it isn't.
overcast 4y ago
Thanks, I'll stick with my battle hardened manual gearbox, until I ride this car into the ground. Maybe I'm turning into a grumpy old man, but I want nothing to do with the lack of physical buttons, giant touchscreens, and fly by wire EVERYTHING in these cars.
- saxonww 4y ago
  Would it be so bad if you actually get the specifications for this stuff? I assume/hope it's so hard because of all the safety regulations applied to cars; the amount of effort this person already has had to put into figuring out how a gear shifter works is sad.
- forgingahead 4y ago
  Wish I could upvote you 1000 times - rented a car last week and couldn't figure out how to control the damn AC in it. Gear shift was a turning knob like I was tuning my radio, not to mention the iPad staring me in the face while I tried to drive. Like TVs, I think there is a decent sized market for "dumb cars" - will any company step up to make them though?
  - ricardobeat 4y ago
    Those are user interface design failures, not a direct consequence of the switch to electronics & automation. There are modern cars that are very pleasant to use (Hyundai Ioniq / Kona are my favorites), while others that have the exact same feature set are terrible (BMW i3, Nissan Leaf).
    - Hellbanevil 4y ago
  - isatty 4y ago
    Let me guess, one of the new Ford SUVs? Happened to me too, wtf was ford thinking with the circular gear selector and AC controlled by a damn screen?
tehwebguy 4y ago
This is cool! I’m currently trying to update the CAN (early Ibus) setup I have connected to E36’s CD changer port. I’m able to receive messages just fine on an Arduino via MCP2025 using ian332isport’s IBus library but I can’t send messages. Just tried using the apparently better Melexis TH3122.4 instead of the MCP but other than sending Vreg power it doesn’t seem to work (and instantly heats up to dangerous temperatures). If anyone happens to be working on something similar hit me up!
- llamajams 4y ago
  Are you using the right transceiver? Looks like MCP202 is for the LIN bus which is a completely different physical standard. There are also multiple different can standards, and I don't think Arduino can support the higher speed versions.
  - tehwebguy 4y ago
    Frankly I am not sure! My car’s bus is only between radio & CD, it seems a little bit less standard and most of the discussions I see are about the next generation (E46) that have loads of other components connected.
    - llamajams 4y ago
      Got a diagram of your setup?
  - maxerickson 4y ago
    It's not a 'CAN' can. https://maakbaas.com/bluetooth-cd-changer-emulator/logs/from-idea-to-prototype/ https://maakbaas.com/bluetooth-cd-changer-emulator/logs/from...
- touchy 4y ago
  Oh the melexis... I had the heat up issue when powering from both USB and the 12v car supply. I snipped the 5v power from the USB line and that allowed me to serial into the teensy and read data. Iirc the melexis supplys 5v from one of it's pins.
post_break 4y ago
Not sure what vehicle this is going into but wouldn't a push button selector be better? Ever since getting my Accord gear shifters look so old hat.
- techwiz137 4y ago
  Which year?
  - post_break 4y ago
    2021 https://imgur.com/a/svq7rfR https://imgur.com/a/svq7rfR
    - spaceywilly 4y ago
      Eek. It seems like there’s a risk that you could push N instead of D when trying to shift from reverse into drive. This could be very dangerous in certain situations, like if you’re backing out of a parking spot onto a busy road.
- woobar 4y ago
  This one provides manu-matic mode, which you can operate without looking at buttons. Not sure if this is a requirement for a new car though.
- tyingq 4y ago
  Push button gear selection was available for many cars between roughly 1956-1964 also. https://www.macsmotorcitygarage.com/the-motor-citys-push-button-age/ https://www.macsmotorcitygarage.com/the-motor-citys-push-but...
- Sebb767 4y ago
  Personal preference, maybe. I, for one, love those old style shifters. The new Audi A3 just has a small knob and to me it looks like you'd turn on an RC car you'd got for 10$ in a cheap knock-off store, not something from the entry-level luxury segment.
Unklejoe 4y ago
There’s a BMW factory level diagnostic program called Tool32 that might help when trying to reverse engineer stuff like this. I don’t think there’s a way to legitimately get ahold of this software though… Anyway, it has a bunch of test operations you can perform. For example, you can set the individual gauges in the gauge cluster to specific values, etc. Perhaps there are some tests for the shifter and you can sniff the bus as they’re performed? These are all done over the OBD port so it shouldn’t be that hard.
- t0mas88 4y ago
  I think one of the e-sys or related ISTA etc tools can move the gear selector. Because the hardware is able to move itself for example from the M/S mode (tilted left) back to center when it goes into park. And I've seen that done via diagnostics, but I'm not sure it was a function of the selector or whether the selector responds to some kind of "engine shutting off" message that it gets from another module.
  - halifaxbeard 4y ago
    Yes. The depth of BMW diagnosis tools is impressive. Even more impressive has been the work of scapy around the debug and diagnosis protocols BMW uses. Check it out: https://github.com/secdev/scapy/blob/master/scapy/contrib/automotive/bmw/definitions.py https://github.com/secdev/scapy/blob/master/scapy/contrib/au...
    - t0mas88 4y ago
      Cool, thanks for sharing!
- kiwidrew 4y ago
  There's a good chance that all of the components in the car have similar/identical command sets for test/debug operations, even if the individual components have been produced by different OEMs.
gumby 4y ago
Why do cars with automatic transmission have shifter rods at all? A button would be sufficient.
- dagmx 4y ago
  For familiarity, especially since many automatic shifters have a pseudo-manual mode to shift up and down. also in case the manufacturer shares the center console part with models that have fully manual transmission.
- hangonhn 4y ago
  I don’t know if the shifter is strictly necessary but I am glad it takes two actions to shift, especially for reverse and forward. It’s also really nice having the shifter because it’s this relatively big control surface I can grab and control without looking down. I have that exact model of BMW and I often use the shifter to quickly put the car into sports mode for overtaking. They have another button to do something similar but there is no way I can do that while overtaking. The move shifter left maneuver is easy to do while keeping my eyes on the road.
  - t0mas88 4y ago
    Exactly. Pressing the mode selector switch a few times to get it to sport/sport+ takes much more looking down compared to pushing the gear selector left while you keep eyes on the road to think about a quick overtake. And this is for cars that aren't 90% touch-screen controlled like some recent models from other brands.
    - Hamuko 4y ago
      >pushing the gear selector left Pushing the gear selector left is actually terrible because (at least in the old BMW shifter) the cables inside the selector are way too tight and they will wear down as you move the shifter. https://www.e90post.com/forums/showpost.php?s=9c79f1c5ddd4ce78a5a2c5be945bd8a6&p=11663805&postcount=5 https://www.e90post.com/forums/showpost.php?s=9c79f1c5ddd4ce...
  - 4y ago
bri3d 4y ago
The debug protocols for XC2xxx are documented and you can interface with the device using an Infineon MiniWiggler. Unless the core or flash protection has been enabled, which is not likely on an "auxiliary" control unit like this, you can read/write flash and possibly also step-debug. You should be able to use the bootstrap loader startup mode and Infineon MemTool to read and write the device. The core IP is called C166S V2 and IDA does an OK job disassembling it. Unfortunately the instruction set is quite nasty anyway so it's not pleasant to reverse engineer even when the tooling works. I agree that coming from the "outside in" might be easier than coming from the "inside out," especially if you are able to acquire the internal BMW powertrain-CAN documentation which will make this project very easy. Infineon do the best job of producing documentation of any major automotive CPU vendor, IMO. Their toolchains and user manuals are both available and much easier to understand than for example Renesas or Freescale.
- nneonneo 4y ago
  Since you have at least one working message, 0x202, and the ability to disassemble the code, one thing to try would be to search for spots in the code where that gets used as an operand or gets loaded from memory. Unless they use a switch statement (unlikely if the codes are so far apart), there’s likely to be an “if code == 0x202” somewhere that would help narrow down the input handling code. If you’re really lucky, all the other valid codes will be sitting in the same function, which (if nothing else) will make your fuzzing efforts a lot more targeted.
natch 4y ago
Is anyone going to tell him that EVs only have one gear? Good ones, anyway… I guess there is always reverse and neutral though.
- speedgoose 4y ago
  The author explains it in the beginning of the article. And the Porsche Taycan has two gears and it is considered good. Though it may be better with only one fixed gear, I heard that you can feel the gearshift.
  - natch 4y ago
    I was specifically excluding Taycan, which is, let’s just say, Porche’s first effort in this space. Edit: I see what you mean about him mentioning it... missed that in my first quick look. Seems it’s my day to be an idiot on the Internet.
  - timc3 4y ago
    I like that it has two gears (I own one).
givemeethekeys 4y ago
Any car maker that uses a BMW transmission uses the same exact gear selector. Your Alfa Romeos, Morgans, Toyota Supras are all BMWs and there's a gear selector to remind you of it every single day. I'd love some insight as to why - was it contractual? Are car makers lazy?
- piperswe 4y ago
  I'm not aware of any modern BMW-made automatic transmissions, BMW has been using ZF transmissions in all of their modern automatic cars that I know of. You'll find a ZF8HP in most of BMW's modern vehicles, as well as many Chrysler and a few Volkswagen vehicles [1]. BMW, Chrysler (including subsidiaries, especially Jeep), and Volkswagen (including subsidiaries, especially Audi) all have quite different shifters [2] [3] [4], but they share transmission families in many vehicles. [1]: https://en.wikipedia.org/wiki/ZF_8HP_transmission#Applications https://en.wikipedia.org/wiki/ZF_8HP_transmission#Applicatio... [2]: https://images.dealer.com/evox/stills_0640/MY2022/15237/15237_st0640_087.jpg https://images.dealer.com/evox/stills_0640/MY2022/15237/1523... [3]: https://carbuzz.com/cars/jeep/grand-cherokee-l/photos-interior#15 https://carbuzz.com/cars/jeep/grand-cherokee-l/photos-interi... [4]: https://media.ed.edmunds-media.com/audi/a6/2022/oem/2022_audi_a6_sedan_prestige_shf_oem_1_1600x1067.jpg https://media.ed.edmunds-media.com/audi/a6/2022/oem/2022_aud... For the shifter images, I specifically chose vehicles that have a ZF8HP transmission.
  - timc3 4y ago
    And they are tuned differently in different vehicles and different manufacturers. BMW does it the best IMHO out of those using that ZF transmission.
  - givemeethekeys 4y ago
    Check these out: Alfa Romeo: https://cdn.jdpower.com/20%20alfa%20giulia%20dash%20sessions.jpg https://cdn.jdpower.com/20%20alfa%20giulia%20dash%20sessions... Morgan Aero 8: https://www.autocar.co.uk/sites/autocar.co.uk/files/styles/gallery_slide/public/images/car-reviews/first-drives/legacy/morgan-2019-8085h.jpg?itok=gBtVLsSd https://www.autocar.co.uk/sites/autocar.co.uk/files/styles/g... Toyota Supra: https://pictures.topspeed.com/IMG/jpg/201905/toyota-supra---drive-57.jpg https://pictures.topspeed.com/IMG/jpg/201905/toyota-supra---... All of them seem to share the same iDrive style that BMW has in their automatics. It made me think they share BMW transmissions too.
ricardobeat 4y ago
That massive board for what is essentially a fancy D-Pad sounds like extreme overkill. Is it actually more reliable than an analog circuit?
- chinabot 4y ago
  Over complex control systems are the reason I have stuck to cars from the last century for conversions, my 1990 hilux had exactly 1 microcontroller in the ECU which went straight in the bin when the electric motor went in. I also stuck with a manual gearbox even though it rarely gets out of 3rd. My other 1996 BMW 528i conversion has been on going for 3 years due to over-complex engineering, I ended up throwing out the automatic transmission and am now using a manual transmission fixed in 3rd gear, basically using the auto selector to select R or D only, the digital logic to get a 1996 528i auto transmission selector working is just a few diodes and resistors.
neuralRiot 4y ago
Usually what i do in cases like these, is to to take a trace of the CAN bus on a working vehicle and then replay this data to the DUT selecting and deselecting different IDs, then i apply random values to different bytes of the responding IDs and observe the reaction. It can be time consuming but more productive that trying to contact OEMs. Also DBC files can be of some help.

140 points by zdw 4y ago

I read like halfway through the article and felt like this hardware was, in classic German car fashion, very over-engineered for the relatively simple purpose of sending one of 5-6 signals to a transmission controller.

KerrAvon 4y ago
On one hand, you really do not want this part to fail. On the other, why is it this complicated in the first place? These overcomplicated shift levers that you need to watch a video to understand seem to be an industry fad — one of them in a Chrysler product (IIRC) killed a Star Trek actor a few years ago.
- amluto 4y ago
  Tactile feedback (like something that actually locks into a park position when it’s in park) is genuinely useful. Tesla uses a little lever with four possible momentary positions. There is no way to feel whether you have actually selected the correct mode. You’re choices are to either look at the instrument cluster and read the gear status or to actually try driving the car. This is made worse by the fact that, on level ground with creep off, park and drive behave identically unless someone presses the accelerator or tries pushing the car. On the flip side, I’ve driven a BMW with a really amazing 2D joystick with software controlled detents corresponding to buttons on the infotainment screen. I’m not convinced it’s a good idea, but the engineering is awesome.
  - doubled112 4y ago
    I don’t like a lot of the UI/UX decisions in modern cars. Every manual transmission I’ve ever driven has given an incredible amount of tactile feedback when you get it wrong. You know you’re parked because you’ve pulled a (relatively) big lever. A little knob or momentary buttons make me uncomfortable. I’d be waiting for feedback but never receiving it. Another example of waiting for something to happen, then nothing happens is start/stop engines. My foot goes down, nothing happens, I give more fuel, still nothing, engine starts and we’re really going. I’m sure I’d get used to it, but I don’t like it. Just do what you’re told, car.
    - lttlrck 4y ago
      start/stop isn't triggered by the accelerator. The engine starts immediately when the brake is released. For most drivers it is unnoticeable. I don't like it but that's because there is little intelligence deciding when it should stop in the first place, though you can kind of regulate it by being extremely light on the pedal.
    - vel0city 4y ago
      As someone else mentioned, start/stop isn't usually triggered by the gas pedal but by releasing the brake. You're probably pretty quick to go from the brake to the gas for your car's start/stop, practice getting off the brake a hair earlier than you do currently. You probably won't roll much since you've got a dead engine holding the car, so don't worry about needing to be quick. I've driven some cars with start/stop and while it was a bit of a different feel for it originally I managed to get the timing down pretty well to have the car do what I wanted. Start/stop isn't driven by a random number generator you can figure out when it'll kill it and how long it goes from getting off the brake to the time it starts. Then it's just like every other tool in the car.
- elvis70 4y ago
  Yes, it was a 2015 Jeep Grand Cherokee https://www.nbcnews.com/business/autos/death-star-trek-actor-highlights-concerns-about-faulty-electronic-shifters-n595751 https://www.nbcnews.com/business/autos/death-star-trek-actor...
- wil421 4y ago
  The shifter was a Bosch part IIRC and was very similar to Audi shifters. Since then if you open your door and depress the brake it will automatically go into park. They also changed the shifter in 2016. 2014/15 model Grand Cherokees have it and many people complained about it.
- izacus 4y ago
  It truly is bizarre - I've driven a lot of cars lately and this exact BMW shifter took the cake of the most unintutitive and annoying to use by far. (And it's not even the most dumbass UX decision in that BMW by far.)
  - RedShift1 4y ago
    I don't get it. All these joystick gear selectors work the same. Push and hold a button and move it to the setting you want. What is unintuitive and annoying about this?
    - gonesilent 4y ago
      Chrysler's attempt at a reimagined shifter killed Star Trek's Chekov. Couldn't tell when it was in park...
      - sgt 4y ago
        This type of technology has to work even when you have a "weak" moment of lapse in judgement. Everyone has those, at the very least a few in your adult lifetime.
    - izacus 4y ago
      Ah sorry, the 1 series I just drove also had an "unlock" button on the left side so you had to hold it in a rather unnatural way to get it to move around. And the separate "P" button is also something that kept throwing me off. In comparison, Mazda I drove had much much simpler approach - grab the stick, push it all the way forward for Park, push it all the way back for Drive. That's it. The "unlock" button was under the index finger so you just grabbed it naturally. (In general, Mazda felt much better thought out inside than VWs, BMWs and MBs I drove.)
  - t0mas88 4y ago
    Exact opposite experience for me, I can use this thing without looking and it does exactly what's expected. It also does manual shifting the right way around, pull to shift up, push to shift down. That's how every sequential racing gearbox works. But somehow a lot of non-sports brands do their manual control the wrong way around.
deleted 4y ago
[deleted]

jjtheblunt 4y ago

https://www.bmw.de/de/shop/ls/dp/physical-goods/12556 https://www.bmw.de/de/shop/ls/dp/physical-goods/12556 explains what GWS is...as mentioned in the article

closewith 4y ago
To save a click, GWS is Gangwahlschalter or gear selector switch.
- dtgriscom 4y ago
  "Gear Which Switch"?
  - jjtheblunt 4y ago
    wa"hlen is to choose. which is welche. perhaps cognates

techwiz137 4y ago

It is very sad that a lot of older automatics needed actual mechanical linkages instead of entirely digital signals. It would've allowed some pretty custom gear selectors that would've enabled even more mods by freeing up space in the car interior.

hotpotamus 4y ago
There were push button automatics in the 50's. But for the life of me I've never seen the problem with a column shifter which was normal when I learned to drive a car in the late 90's.
- tadfisher 4y ago
  The push buttons were also mechanically linked! At least Chrysler selectors such as the one used in the Plymouth Valiant, they actuated cables to open/close fluid paths in the transmission.
  - hotpotamus 4y ago
    Yeah, I'm aware that old auto transmissions had what - valve bodies? - analog computers to apply logic on when to shift; they'd have to have something. I just don't think the linkage was all that important a feature - mechanical or electronic seem to both be flexible enough to do the job. I mostly drive manuals, but the column shifter for autos seems the most utterly logical way to put transmission control right at your hands. It seems like putting it on top of where a transmission hump might go (but probably doesn't in a modern car with a transverse engine) is just pretending to be something it isn't.

overcast 4y ago

Thanks, I'll stick with my battle hardened manual gearbox, until I ride this car into the ground. Maybe I'm turning into a grumpy old man, but I want nothing to do with the lack of physical buttons, giant touchscreens, and fly by wire EVERYTHING in these cars.

saxonww 4y ago
Would it be so bad if you actually get the specifications for this stuff? I assume/hope it's so hard because of all the safety regulations applied to cars; the amount of effort this person already has had to put into figuring out how a gear shifter works is sad.
forgingahead 4y ago
Wish I could upvote you 1000 times - rented a car last week and couldn't figure out how to control the damn AC in it. Gear shift was a turning knob like I was tuning my radio, not to mention the iPad staring me in the face while I tried to drive. Like TVs, I think there is a decent sized market for "dumb cars" - will any company step up to make them though?
- ricardobeat 4y ago
  Those are user interface design failures, not a direct consequence of the switch to electronics & automation. There are modern cars that are very pleasant to use (Hyundai Ioniq / Kona are my favorites), while others that have the exact same feature set are terrible (BMW i3, Nissan Leaf).
  - Hellbanevil 4y ago
- isatty 4y ago
  Let me guess, one of the new Ford SUVs? Happened to me too, wtf was ford thinking with the circular gear selector and AC controlled by a damn screen?

tehwebguy 4y ago

This is cool! I’m currently trying to update the CAN (early Ibus) setup I have connected to E36’s CD changer port. I’m able to receive messages just fine on an Arduino via MCP2025 using ian332isport’s IBus library but I can’t send messages. Just tried using the apparently better Melexis TH3122.4 instead of the MCP but other than sending Vreg power it doesn’t seem to work (and instantly heats up to dangerous temperatures). If anyone happens to be working on something similar hit me up!

llamajams 4y ago
Are you using the right transceiver? Looks like MCP202 is for the LIN bus which is a completely different physical standard. There are also multiple different can standards, and I don't think Arduino can support the higher speed versions.
- tehwebguy 4y ago
  Frankly I am not sure! My car’s bus is only between radio & CD, it seems a little bit less standard and most of the discussions I see are about the next generation (E46) that have loads of other components connected.
  - llamajams 4y ago
    Got a diagram of your setup?
- maxerickson 4y ago
  It's not a 'CAN' can. https://maakbaas.com/bluetooth-cd-changer-emulator/logs/from-idea-to-prototype/ https://maakbaas.com/bluetooth-cd-changer-emulator/logs/from...
touchy 4y ago
Oh the melexis... I had the heat up issue when powering from both USB and the 12v car supply. I snipped the 5v power from the USB line and that allowed me to serial into the teensy and read data. Iirc the melexis supplys 5v from one of it's pins.

post_break 4y ago

Not sure what vehicle this is going into but wouldn't a push button selector be better? Ever since getting my Accord gear shifters look so old hat.

techwiz137 4y ago
Which year?
- post_break 4y ago
  2021 https://imgur.com/a/svq7rfR https://imgur.com/a/svq7rfR
  - spaceywilly 4y ago
    Eek. It seems like there’s a risk that you could push N instead of D when trying to shift from reverse into drive. This could be very dangerous in certain situations, like if you’re backing out of a parking spot onto a busy road.
woobar 4y ago
This one provides manu-matic mode, which you can operate without looking at buttons. Not sure if this is a requirement for a new car though.
tyingq 4y ago
Push button gear selection was available for many cars between roughly 1956-1964 also. https://www.macsmotorcitygarage.com/the-motor-citys-push-button-age/ https://www.macsmotorcitygarage.com/the-motor-citys-push-but...
Sebb767 4y ago
Personal preference, maybe. I, for one, love those old style shifters. The new Audi A3 just has a small knob and to me it looks like you'd turn on an RC car you'd got for 10$ in a cheap knock-off store, not something from the entry-level luxury segment.

Unklejoe 4y ago

There’s a BMW factory level diagnostic program called Tool32 that might help when trying to reverse engineer stuff like this. I don’t think there’s a way to legitimately get ahold of this software though… Anyway, it has a bunch of test operations you can perform. For example, you can set the individual gauges in the gauge cluster to specific values, etc. Perhaps there are some tests for the shifter and you can sniff the bus as they’re performed? These are all done over the OBD port so it shouldn’t be that hard.

t0mas88 4y ago
I think one of the e-sys or related ISTA etc tools can move the gear selector. Because the hardware is able to move itself for example from the M/S mode (tilted left) back to center when it goes into park. And I've seen that done via diagnostics, but I'm not sure it was a function of the selector or whether the selector responds to some kind of "engine shutting off" message that it gets from another module.
- halifaxbeard 4y ago
  Yes. The depth of BMW diagnosis tools is impressive. Even more impressive has been the work of scapy around the debug and diagnosis protocols BMW uses. Check it out: https://github.com/secdev/scapy/blob/master/scapy/contrib/automotive/bmw/definitions.py https://github.com/secdev/scapy/blob/master/scapy/contrib/au...
  - t0mas88 4y ago
    Cool, thanks for sharing!
kiwidrew 4y ago
There's a good chance that all of the components in the car have similar/identical command sets for test/debug operations, even if the individual components have been produced by different OEMs.

gumby 4y ago

Why do cars with automatic transmission have shifter rods at all? A button would be sufficient.

dagmx 4y ago
For familiarity, especially since many automatic shifters have a pseudo-manual mode to shift up and down. also in case the manufacturer shares the center console part with models that have fully manual transmission.
hangonhn 4y ago
I don’t know if the shifter is strictly necessary but I am glad it takes two actions to shift, especially for reverse and forward. It’s also really nice having the shifter because it’s this relatively big control surface I can grab and control without looking down. I have that exact model of BMW and I often use the shifter to quickly put the car into sports mode for overtaking. They have another button to do something similar but there is no way I can do that while overtaking. The move shifter left maneuver is easy to do while keeping my eyes on the road.
- t0mas88 4y ago
  Exactly. Pressing the mode selector switch a few times to get it to sport/sport+ takes much more looking down compared to pushing the gear selector left while you keep eyes on the road to think about a quick overtake. And this is for cars that aren't 90% touch-screen controlled like some recent models from other brands.
  - Hamuko 4y ago
    >pushing the gear selector left Pushing the gear selector left is actually terrible because (at least in the old BMW shifter) the cables inside the selector are way too tight and they will wear down as you move the shifter. https://www.e90post.com/forums/showpost.php?s=9c79f1c5ddd4ce78a5a2c5be945bd8a6&p=11663805&postcount=5 https://www.e90post.com/forums/showpost.php?s=9c79f1c5ddd4ce...
- 4y ago

bri3d 4y ago

The debug protocols for XC2xxx are documented and you can interface with the device using an Infineon MiniWiggler. Unless the core or flash protection has been enabled, which is not likely on an "auxiliary" control unit like this, you can read/write flash and possibly also step-debug. You should be able to use the bootstrap loader startup mode and Infineon MemTool to read and write the device. The core IP is called C166S V2 and IDA does an OK job disassembling it. Unfortunately the instruction set is quite nasty anyway so it's not pleasant to reverse engineer even when the tooling works. I agree that coming from the "outside in" might be easier than coming from the "inside out," especially if you are able to acquire the internal BMW powertrain-CAN documentation which will make this project very easy. Infineon do the best job of producing documentation of any major automotive CPU vendor, IMO. Their toolchains and user manuals are both available and much easier to understand than for example Renesas or Freescale.

nneonneo 4y ago
Since you have at least one working message, 0x202, and the ability to disassemble the code, one thing to try would be to search for spots in the code where that gets used as an operand or gets loaded from memory. Unless they use a switch statement (unlikely if the codes are so far apart), there’s likely to be an “if code == 0x202” somewhere that would help narrow down the input handling code. If you’re really lucky, all the other valid codes will be sitting in the same function, which (if nothing else) will make your fuzzing efforts a lot more targeted.

natch 4y ago

Is anyone going to tell him that EVs only have one gear? Good ones, anyway… I guess there is always reverse and neutral though.

speedgoose 4y ago
The author explains it in the beginning of the article. And the Porsche Taycan has two gears and it is considered good. Though it may be better with only one fixed gear, I heard that you can feel the gearshift.
- natch 4y ago
  I was specifically excluding Taycan, which is, let’s just say, Porche’s first effort in this space. Edit: I see what you mean about him mentioning it... missed that in my first quick look. Seems it’s my day to be an idiot on the Internet.
- timc3 4y ago
  I like that it has two gears (I own one).

givemeethekeys 4y ago

Any car maker that uses a BMW transmission uses the same exact gear selector. Your Alfa Romeos, Morgans, Toyota Supras are all BMWs and there's a gear selector to remind you of it every single day. I'd love some insight as to why - was it contractual? Are car makers lazy?

piperswe 4y ago
I'm not aware of any modern BMW-made automatic transmissions, BMW has been using ZF transmissions in all of their modern automatic cars that I know of. You'll find a ZF8HP in most of BMW's modern vehicles, as well as many Chrysler and a few Volkswagen vehicles [1]. BMW, Chrysler (including subsidiaries, especially Jeep), and Volkswagen (including subsidiaries, especially Audi) all have quite different shifters [2] [3] [4], but they share transmission families in many vehicles. [1]: https://en.wikipedia.org/wiki/ZF_8HP_transmission#Applications https://en.wikipedia.org/wiki/ZF_8HP_transmission#Applicatio... [2]: https://images.dealer.com/evox/stills_0640/MY2022/15237/15237_st0640_087.jpg https://images.dealer.com/evox/stills_0640/MY2022/15237/1523... [3]: https://carbuzz.com/cars/jeep/grand-cherokee-l/photos-interior#15 https://carbuzz.com/cars/jeep/grand-cherokee-l/photos-interi... [4]: https://media.ed.edmunds-media.com/audi/a6/2022/oem/2022_audi_a6_sedan_prestige_shf_oem_1_1600x1067.jpg https://media.ed.edmunds-media.com/audi/a6/2022/oem/2022_aud... For the shifter images, I specifically chose vehicles that have a ZF8HP transmission.
- timc3 4y ago
  And they are tuned differently in different vehicles and different manufacturers. BMW does it the best IMHO out of those using that ZF transmission.
- givemeethekeys 4y ago
  Check these out: Alfa Romeo: https://cdn.jdpower.com/20%20alfa%20giulia%20dash%20sessions.jpg https://cdn.jdpower.com/20%20alfa%20giulia%20dash%20sessions... Morgan Aero 8: https://www.autocar.co.uk/sites/autocar.co.uk/files/styles/gallery_slide/public/images/car-reviews/first-drives/legacy/morgan-2019-8085h.jpg?itok=gBtVLsSd https://www.autocar.co.uk/sites/autocar.co.uk/files/styles/g... Toyota Supra: https://pictures.topspeed.com/IMG/jpg/201905/toyota-supra---drive-57.jpg https://pictures.topspeed.com/IMG/jpg/201905/toyota-supra---... All of them seem to share the same iDrive style that BMW has in their automatics. It made me think they share BMW transmissions too.

ricardobeat 4y ago

That massive board for what is essentially a fancy D-Pad sounds like extreme overkill. Is it actually more reliable than an analog circuit?

chinabot 4y ago
Over complex control systems are the reason I have stuck to cars from the last century for conversions, my 1990 hilux had exactly 1 microcontroller in the ECU which went straight in the bin when the electric motor went in. I also stuck with a manual gearbox even though it rarely gets out of 3rd. My other 1996 BMW 528i conversion has been on going for 3 years due to over-complex engineering, I ended up throwing out the automatic transmission and am now using a manual transmission fixed in 3rd gear, basically using the auto selector to select R or D only, the digital logic to get a 1996 528i auto transmission selector working is just a few diodes and resistors.

neuralRiot 4y ago

Usually what i do in cases like these, is to to take a trace of the CAN bus on a working vehicle and then replay this data to the DUT selecting and deselecting different IDs, then i apply random values to different bytes of the responding IDs and observe the reaction. It can be time consuming but more productive that trying to contact OEMs. Also DBC files can be of some help.