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Hacking the E30 Instrument Cluster for Computers?

Posted by Earendil 
I'll make this post really short.

I'm a soon to be graduate in Computer Science.
I am not an Electrical Engineer.
Due to youth, I have more ambitions than I know what to do with, or could ever archive.
I'm about to replace my IS, and so will have a spare one to play around with.

If I knew how to get input from the instrument cluster (or the ECU) into a computer port, I could write a program to track and graph all observable data over a period of time, and save said data.

Anyone know of such a project?
Anyone one ever thought to themselves that they could create a hardware interface for our simple little wired cluster, but didn't have the programming knowledge to put it to use?
Obviously, hacking our cluster up is possible to some degree




I know this isn't an extreme car modification forum, but I love you guys, and thought I'd ask here first :-)

Cheers,
~Tyler

ps
10 minutes on google hasn't turned up much of anything useful
pss
Hopefully this still seems like a good idea when I haven't had a couple beers...
i know zero about what you are wanting to do, but...

how about talking to the guy who did this? he is the owner of R3Vlimited.com. pretty nice guy.

[jalopnik.com]

videos


here is a thread, i dont know how much he goes into the technical stuff though.
[r3vlimited.com];


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Earendil


If I knew how to get input from the instrument cluster (or the ECU) into a computer port, I could write a program to track and graph all observable data over a period of time, and save said data.


And then do what with this data?
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John Yust
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Earendil


If I knew how to get input from the instrument cluster (or the ECU) into a computer port, I could write a program to track and graph all observable data over a period of time, and save said data.


And then do what with this data?

Maybe use it to run a wire mess display of the fuel mapping as it changes in real time...that would be cool thumbs up
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Archeo-peteriX


Maybe use it to run a wire mess display of the fuel mapping as it changes in real time...that would be cool thumbs up

Wire mess? You mean like that mess under the dash that looks like spaghetti? smiling smiley
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John Yust
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Archeo-peteriX


Maybe use it to run a wire mess display of the fuel mapping as it changes in real time...that would be cool thumbs up

Wire mess? You mean like that mess under the dash that looks like spaghetti? smiling smiley

That might take a little more programming but I was thinking of something like this...


With the right info, the program could update each of those mesh point for a real time animated display smiling smiley








Oh...I just spotted my type :o
An interface to record data would be really handy for trouble shooting but once the problem is located, probably would just be entertaining. The fuel meter is something I watch a lot and it helps me get great mileage. Just cannot seem to compensate for the cold weather though. The lower the temp, the poorer my mileage. Not sure why. Maybe this computer link could explain why and allow corrections.

Bob in Everett
It could be useful in a number of ways, mostly trouble shooting, but there is certainly a fun factor as well. Oh yeah, and self education ;-)

Personally, my poor baby has seen 250+ thousand miles, and a problem I'm finding is that the wiring isn't holding up real well. I'm starting to see some really quirky behavior that is extremely hard to diagnose. One of the reasons it is so hard, is that unlike a piece of hardware, that generally dies and stays dead, electrical problems can be intermittent. And Murphey's law does have a clause in there about such electrical problems fixing themselves right about the time you pull into the garage ;-)

Initial ideas:
Car acceleration vs a baseline.
While getting some sort of HP rating, or anything close to dyno results would be hard, requiring accurate weight among other things, comparing vehicle acceleration vs a baseline would NOT be hard. Imagine that you figure out what your car's "power" is as an arbitrary value. Once you have that value you can compare results to it to figure out if your car has gained or lost power due to adding an "improvement", or because you suspect something is wrong.

For similar reasons as the above, you could get fuel consumption out of your car in more detail.
This might depend on what all the IC knows. If it is aware of the fuel rate as a value, than this is easy. If it is only aware of the mpg, than you would have to derive the fuel consumption based on velocity and mpg.
If a direct fuel consumption rate were possible to read, then you could watch your car at idle and figure out if it was below/above a "norm".

If high sampling rates were possible, you may be able to monitor your RPM values vs your injectors and figure out exactly which cylinder wasn't pulling it's weight. Often times I can hear my car missing or hesitating, but I'll be darned if I know which one it is.

Our CO2 sensors produce values that jump all over the place, and our ECU averages those to make the info useful. This is why if you ever plug a voltmeter up to your CO2 line it will jump up and down. Being able to capture that data and average it would enable the CO2 readings to be worth something.

Because we could be aware of the RPM when looking at all of the above, you could figure out if a particular problem only showed up at certain RPM ranges, or above certain RPMs indicating a fuel/air deliver problem.

But who knows. There are a million technical things that could get in the way, not to mention personal life things, so I don't want to get anyone's hopes up. But I think it's worth exploring and pondering.
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Earendil
It could be useful in a number of ways, mostly trouble shooting, but there is certainly a fun factor as well. Oh yeah, and self education ;-)

Good for you!

I know this is dumb - How about some audio signal attached to the warning lights? Like a chime for the oil pressure light? (OK, I know it's not sexy, but it is practical.) Or if you were feeling really feisty you could trigger an audio file that said "Grease or Die Fool !" or "Please find gas soon."

:-) Kelly
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Kelly
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Earendil
It could be useful in a number of ways, mostly trouble shooting, but there is certainly a fun factor as well. Oh yeah, and self education ;-)

Good for you!

I know this is dumb - How about some audio signal attached to the warning lights? Like a chime for the oil pressure light? (OK, I know it's not sexy, but it is practical.) Or if you were feeling really feisty you could trigger an audio file that said "Grease or Die Fool !" or "Please find gas soon."

:-) Kelly

Well, since I don't intend to build an in dash computer (yet), I would just plug this straight into my laptop with software running on it that I write. If you want to provide your own laptop, I'll provide software that will ridicule you in any way you want ;-)

Side note: my car has left me stranded more times because I've run out of gas, than because she actually breaks down. Once I hit nasty wash boards, sucked some air bubbles, then parked her off the road on an incline such that any remaining gas was too far away from the intake.
Second and third time were because my gas gauge only reads the top half of my tank, and so I relied on my gas warning light to tell me when to fill up...up until, you guessed it, the gas light burnt out ;-)
I just remembered a couple of things that might get you started.

Ove Kvam has a software program that calculates HP from the rpm(noted by a sound pick up I think). He says it is fairly accurate. Perhaps he would be willing to share it with you as he has done in the past. Give him a PM and see what he says.

Jaffar once built a computer into his car. I don't remember what he used it for but the installation info might be of use to you as well.
Perhaps he would share this with you. It was a couple of forum 'revisions' ago so it's not archived anywhere sad smiley

I like Kelly's idea of sexy messages..."Hey there big boy, I'm getting a little dry; wanna break out the 15w50" winking smiley
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Earendil
Personally, my poor baby has seen 250+ thousand miles, and a problem I'm finding is that the wiring isn't holding up real well. I'm starting to see some really quirky behavior that is extremely hard to diagnose.

Hi Earendil,

Your statement above is giving me the worries. As in "Should I just buy a new wiring harness now and store it for future use?" What if I cannot buy one in the future. Would it even be possible to install a new harness? I suppose the dash board, interiors, and trunk liner would need to be removed.

Humm, Kelly - 130,000 miles
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Kelly
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Earendil
Personally, my poor baby has seen 250+ thousand miles, and a problem I'm finding is that the wiring isn't holding up real well. I'm starting to see some really quirky behavior that is extremely hard to diagnose.

Hi Earendil,

Your statement above is giving me the worries. As in "Should I just buy a new wiring harness now and store it for future use?" What if I cannot buy one in the future. Would it even be possible to install a new harness? I suppose the dash board, interiors, and trunk liner would need to be removed.

Humm, Kelly - 130,000 miles

Kelly - I wouldn't worry too much about your wiring. California cars always seem to fair much better than in other places because the climate is so mild. This goes for the wiring too. Extreme cold and humidity can do a number on any cars wiring, that is why a garage kept car is so nice. Extreme heat is another killer. Cars that sit out in the sun and bake are the ones with cracked dashes and split seat leather. All the moisture is baked right out of the interior and paint. Salt is another destructive force on electrical devices. Winter driving is probably the most destructive force for any vehicle. This is my opinion of course, but this is the reason why most Cali cars are worth more than one's from the north east coast. I should also mention that most Californians love their cars more than God so they take extremely good care of them too! B)



Edited 1 time(s). Last edit at 03/10/2009 10:58AM by wodcutr.
God has a car?

Wonder what she drives...and where grinning smiley
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Archeo-peteriX
God has a car?

Wonder what she drives...and where grinning smiley

I think all she has to say is "beamer me up scotty" and off she goes to Venus! eye popping smiley
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wodcutr
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Archeo-peteriX
God has a car?

Wonder what she drives...and where grinning smiley

I think all she has to say is "beamer me up scotty" and off she goes to Venus! eye popping smiley

Well, that will get her motorcycle moving but the E30 will still be parked in that cloud where the Phili Cream Cheeze angel lives winking smiley
How about using your short section of OBC wiring harness? This would give access to lots of useful signals from the IC with no hacking required.

The OBC gets speed, fuel level and fuel rate signals via this interface. You might need to do some hacking in the engine bay (or ECU loom) for coolant temp, air temp, oxygen sensor, throttle position, but the engine revs should be straight forward - a thin wire wound several turns round an HT lead will give you the engine revs as a pulsed signal. All of these signals would probably need to be buffered.

From the OBC plug:
The fuel level will be an analogue voltage proportional to fuel., so would need a buffer and A to D converter.
The speed is a pulsed voltage, so just needs squared up in a comparator and hey presto (like the engine revs).
Not sure what the fuel rate signal does - it comes from the ECU, so could be either. You could just implement both to cover yourself.

You can buy data aquisition cards that would do all or most of this interface stuff for you and allow analogue and digital signals to be seen by the laptop. After that, it's over to you. I would probably start with something like LabView, but then I'm an electronics guy, not a CS guy!

A quick look with google shows up stuff like this:
[www.superlogics.com]
but it only copes with 10v signals - better to find something that would deal direct with the 12v signals.

Sounds like a cool project. Good luck!

---

I tidied my tools, stood back, admired my work, and the garage door fell off…
If you are going to take all the time to get the info just from the cluster and possibly from the ECU, have you looked in to megasquirt. That way to can also tune what you dont like. I know that it would be a ton more work to do this. But there is software already written to run e30s which from what I understand is over half the megasquirt battle (please correct me if I am wrong)

I rode with a friend once using something like megasquirt and he wanted to race someone, pulled out this laptop changed the fuel mapping. We went from 38 mpg to 12 and up to somewhere in the 650 hp range. It was really cool to see.

______________________________________________
87 325e

Still trying to work smart not hard.
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murrayjambo
How about using your short section of OBC wiring harness? This would give access to lots of useful signals from the IC with no hacking required.

That is actually the idea. However I still think of tapping into wires as "hacking". Heck, doing anything to a piece of hardware/software that goes beyond general application is hacking in a sense :-)

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murrayjambo
You can buy data aquisition cards that would do all or most of this interface stuff for you and allow analogue and digital signals to be seen by the laptop. After that, it's over to you. I would probably start with something like LabView, but then I'm an electronics guy, not a CS guy!

Right-o! I'm looking at the Arduino Mega right now, as an overkill solution. Alternatively I may use the regular Arduino for testing, which comes in at around $25 location depending. Right now though I haven't the time, sadly, because I am ironically failing my electronics class here in a my senior year at uni :undecided:

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murrayjambo
Sounds like a cool project. Good luck!

Thanks :-)

Look for updates come end of May.
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jl1371
If you are going to take all the time to get the info just from the cluster and possibly from the ECU, have you looked in to megasquirt. That way to can also tune what you dont like. I know that it would be a ton more work to do this. But there is software already written to run e30s which from what I understand is over half the megasquirt battle (please correct me if I am wrong)

I rode with a friend once using something like megasquirt and he wanted to race someone, pulled out this laptop changed the fuel mapping. We went from 38 mpg to 12 and up to somewhere in the 650 hp range. It was really cool to see.

I have looked into megasquirt a littlebit. However half the fun of this project will be doing it myself for the education value and the experience. The end result is less important, as I probably wouldn't use the gathered information for anything but diagnostic purposes.
And if I succeed, and the process is simple enough, and components cheap enough, I'll do a little DIY writeup and you guys can have fun as well. Going the megasquirt route means that at the end of the day, all I can to do is give you guys the thumbs up or down, spend lots of money, and have no personal fun smiling smiley

Thanks for the idea though!
Hi Earendil,

I know this has been inactive for a few years but was interested in seeing if and how the hack is going? I could see many great uses for a Raspberry Pi / Arduino retrofit to the old system (considering the cost of replacing with 80s oem). There are plenty of people that would love to modernize their e30s, e28s, e24s etc. and could do so with a clean custom look. If you could you have the hack, I could replace the 80s obc with a touch screen and build a menu to look the same as the original amber obc. What do you think?
I could use some of this myself.

My current daily driver is a Mercedes Benz 250D (for the american readers, it is a w124 powered by a 5 cylinder normally aspirated diesel engine.
It came new in 1988 with external thermometer, but the LCD display has gone bad a long time ago. I have an extra cluster, cause the odometer quit, and I am planing to do one good cluster from the two partially broken.

The space where the OEM temperature display goes could use some new display, and the space behind could hold an Arduino or Raspberry Pi, only concern would be the longevity of such devices on board my car, considering the harsh use it endures.
Or an old android phone, running some GPS app, it could serve as an odometer and hour counter.

Any thoughts?
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