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BMW F Series Gear Selector, Part Two: Breakthrough

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Re: BMW F Series Gear Selector, Part Two: Breakthrough

#71

Post by Gordonjcp »

Nullabillity wrote: post #7
mike_pol wrote: post #4

Earlier quoted context omitted.

I appreciate where you’re coming from but experiencing the joy of dual clutch automatics and their shifts in BMWs and Audis that I had the joy to diving might change your mind. The latency you mention is really not there. Admittedly I could not service it if it broke but aren’t cars consumables now?

In what deluded world are items that cost tens of thousands of dollars consumables?! > I appreciate where you’re coming from but experiencing the joy of dual clutch automatics and their shifts in BMWs and Audis that I had the joy to diving might change your mind. Yeah, no thanks. A good manual transmission is a core part of the driving experience.

> Yeah, no thanks. A good manual transmission is a core part of the driving experience.

I learned to drive in manuals (because they're more common in the UK). I currently own two automatics and drive a variety of manuals, automatics and EVs that are kind of inherently "automatic".

I don't see any difference in "driving experience" between manual and automatic. What do *you* think the difference is?

Re: BMW F Series Gear Selector, Part Two: Breakthrough

#72

Post by BoorishBears »

bonestamp2 wrote: post #54
BoorishBears wrote: post #45

Earlier quoted context omitted.

If you're comfortable with slightly shadier methods, there's "grey market" access to most BMW tools. With the F and G series ISTA is the "gold standard"

Can confirm. I paid a guy on a BMW forum about $100 for the vehicle interface, which is ethernet to a J1962 connector (aka "OBD II Port"). That also included the e-sys software (Windows only). A few years later I needed an update to the software and found a guy on ebay who charged me about $75. So, those might be some places to look for this kind of thing.

Pro tip for any BMW owners, MHD is a tuning company that makes great hardware for this.

Even if you're scared of tuning your engine, their dongle originally for that purpose is one of the fastest interfaces and supports Wifi.

The difference in speed is large enough I stopped needing a battery charger to flash my ECU and TCU (would still recommend one though since you are technically playing russian roulette doing that...)

Bonus: If you do care about tuning, they have some excellent off the shelf tunes to go with it

Re: BMW F Series Gear Selector, Part Two: Breakthrough

#73

Post by neuralRiot »

spaceywilly wrote: post #30

This makes me realize how easy it would be to hack a car like this. All you would need to do is sneak into the car and plug in a low profile OBD reader-like device with a cellular modem, and you could send these messages from anywhere. Just with the information in these articles we now know how to spoof the shifter mechanism, I’m sure similar processes could be used to determine steering and throttle controls. All th…

I’m not sure with what purpose would anyone do that. Tracking? Assassination? Stealing? There’s simpler an more effective methods for any of that.

Re: BMW F Series Gear Selector, Part Two: Breakthrough

#74

Post by [deleted] »

bonestamp2 wrote: post #56
bri3d wrote: post #39

Earlier quoted context omitted.

This was true in the mid 2000s, but isn't true on most modern cars. Most modern cars have a Gateway module which sits between the OBD port and the Powertrain CAN busses which the OP is reverse engineering. These Gateway modules only allow specific diagnostics-related messages through to the various backing buses. Now, generally the security on the Gateway module itself isn't great, and diagnostic protocols also aren'…

I do consulting for one OEM and all of their new vehicles over the past couple of years use encrypted bus traffic. So, it is getting much harder for third party tools to communicate with anything that is not mandated by law (most things other than DTCs and Emissions related APIs). The sole purpose is security. Trust me, the engineers don't want to introduce any more complexity than necessary, and that's why it has be…

[deleted]

Re: BMW F Series Gear Selector, Part Two: Breakthrough

#75

Post by paywallasinbeer »

themitigating wrote: post #51
paywallasinbeer wrote: post #33

Earlier quoted context omitted.

It's important to note that just because a CEL is on for a sensor, it doesn't mean that sensor is bad and needs to be replaced. For example, it's possible for a camshaft position sensor to be on for a timing system that is out of sync. It would be a mistake to replace the cam sensor in that scenario. Shotgunning parts isn't always the answer...

It was a 2007 Honda Civic, the 3rd clutch pressure switch measures fluid pressure. P0847 was the code. This means the sensor was sending a voltage value below the acceptable range. The car shifted fine, the fluid was at the proper level, and there were no noticeable driving issues. This would also not continuously read a low voltage reading while changing gears. This led me to believe it's the sensor, which is very i…

I'm glad it was straightforward for you!

Re: BMW F Series Gear Selector, Part Two: Breakthrough

#76

Post by paywallasinbeer »

Gordonjcp wrote: post #69
paywallasinbeer wrote: post #33

Earlier quoted context omitted.

It's important to note that just because a CEL is on for a sensor, it doesn't mean that sensor is bad and needs to be replaced. For example, it's possible for a camshaft position sensor to be on for a timing system that is out of sync. It would be a mistake to replace the cam sensor in that scenario. Shotgunning parts isn't always the answer...

Ooooh, I've got a great story about that. My neighbour's car was at the garage for about three weeks with a No-Crank No-Start fault. The diagnostics said that the crank position sensor was faulty, but the garage said they'd tried two new sensors and a new cam position sensor for good measure, and it still wouldn't work. Their next plan of attack - and bearing in mind they were already about a grand into it - was to s…

Step 1. Replace sensor

2. Replace ECU

3. ???

4. Sell car for scrap

Haha.

Re: BMW F Series Gear Selector, Part Two: Breakthrough

#77

Post by Hellbanevil »

h2odragon wrote: post #9
wolrah wrote: post #6

Earlier quoted context omitted.

> Makes me want to go out and hug my truck, whose gear selector consists of metal sticks and pins. If it's a manual transmission or an ancient automatic, sure, but manual transmission trucks basically haven't existed for a decade or so and every automatic since the mid 90s has an electronic gear selector of some variety. Somehow the world keeps working just fine. The biggest problem that's come up with them has been…

Mine is the last manual v8 Dodge dakota sold, possibly the last made. 230k miles and still have a sliver of the original clutch.

No post body was provided.

Re: BMW F Series Gear Selector, Part Two: Breakthrough

#78

Post by bonestamp2 »

bri3d wrote: post #60
bonestamp2 wrote: post #56

Earlier quoted context omitted.

I do consulting for one OEM and all of their new vehicles over the past couple of years use encrypted bus traffic. So, it is getting much harder for third party tools to communicate with anything that is not mandated by law (most things other than DTCs and Emissions related APIs). The sole purpose is security. Trust me, the engineers don't want to introduce any more complexity than necessary, and that's why it has be…

> because of Massachusetts' right to repair laws, OEM tools are available to anyone (or any shop) that wants to pay for them (in and out of MA). At a price that's meaningless to a hobbyist and steep for an independent shop, sure. Also, the actual implementation of these rules has been stalled for years by Alliance for Automotive Innovation v. Healy. Point me to where I can legally, in a "clean" way, download ODIS for…

> At a price that's meaningless to a hobbyist and steep for an independent shop, sure.

I agree, they're pricey for hobbyists, and I can't speak for all but the I work with is well priced for independent shops. This is not exclusive to automotive though, professional tools in most industries are not priced for hobbyists -- it's easy to lose money on enterprise software if it's priced for hobbyists.

> Also, the actual implementation of these rules has been stalled for years by Alliance for Automotive Innovation v. Healy.

You're thinking about the newer "expanded rights" law. I'm talking about the original 2012 law that the newer law is trying to expand upon:

https://en.wikipedia.org/wiki/2012_Massachusetts_Question_1

Re: BMW F Series Gear Selector, Part Two: Breakthrough

#79

Post by Hellbanevil »

themitigating wrote: post #27
Cthulhu_ wrote: post #16

Earlier quoted context omitted.

I kinda wish, as it stands it feels like decades of different protocols and technologies awkwardly stitched together. In theory everything would be connected on a central bus to a centralized RTOS computer able to read every sensor and adjust everything that needs it 1000x a second (or more), so that anyone could easily hook up a new device or software and subscribe to an event bus, but alas.

Mostly every component on modern cars uses the CAN bus for communication https://en.wikipedia.org/wiki/CAN_bus Many third party companies have made accessories to read information or control devices using it. Cars also have a standard diagnostic port called the OBD2 which you can purchase $10 readers that use bluetooth with your phone. Cars may have much more electronics but with all the sensors it's very easy to kno…

No post body was provided.

Re: BMW F Series Gear Selector, Part Two: Breakthrough

#80

Post by Prcmaker »

phkahler wrote: post #44

A lot of the complexity here is because the gear selector is considered a safety-critical part. They may also consider LED indicators on it as safety-critical information to the driver. Those two things - is the transmission receiving the real intent of the driver, and is the driver being told the actual state of the system - are just the top level. Security is also starting to be a concern, though I think there is r…

I recall driving a borrowed Mercedes in early 2020, the car was maybe two years old, two door coupe, nice but not super sporty, automatic. As is my habit, one of the first things I did was put it in to manually shifted mode. I found with acceleration and braking, coupled with the inertia of the gear knob, gears could be shifted inadvertently. Insult to injury, that inadvertent shift could be enough to trigger a second shift, resulting in some extremely unpredictable vehicle dynamics. A stronger set of centring springs would have been all that was required to easily filter the noise from driver intent.
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