E46 Can Bus Cluster solution

[protomor]

More verbose information can be found here: http://yoshi.e30drifter.com/2019/06/...o-e46-can-bus/

Basically, The thaniel module doesn't work for me because it connects to the LS PCM via the OBD2 port and I want that for my data logger. Also, I'm leaving my factory DME in to run other things on my car.

When you convert your engine to an LS or anything else, you lose RPM and coolant temp (among other things) from your cluster. I also did an M3 rear end conversion so I lost the speedometer as well. Like Thaniel, I plan to use an arduino and a can bus shield to power the cluster. The LS PCM already has a 5v tachometer signal and worst case, I can use a GPS module to feed in my tachometer. I could use a coolant temp sensor but I'm gonna wire up an aftermarket gauge to get a real number instead of the factory dummy gauge.

So far I have the arduino feeding an rpm signal to a stand alone cluster. Since the DME pushes out an rpm of 0 to the gauge, I figure I'll just cut the can bus wires to it and see what happens. This leaves the other lights on the dash and mpg gauge to be blank templates to do other things. At minimum, I should be able to get my tach working again. The speedo is read in with a pwm signal to an analog input to the cluster so I'll need to do a pull up circuit to upscale to 12v, but it should be doable.

[Liquidity]

Does the LCM communicate to the dash via CAN bus? Because you’ll lose your directionals and high beam indicators. I know for a fact they are not directly connected - I’ve had some very strange things happen before - like when I would shut off my directionals, the dash would continue blinking even though the actual lights stopped.

[protomor]

Hmm good point. Let's snip wires and find out! Worst case I would probably run 2 can modules and use the arduino to filter it out.

Sent from my SM-G975U using Tapatalk

[protomor]

Turn signals and LCM functions all still work. Googling says it's done via the k bus system. Looks like the can bus wires are purely for DME specific functions. So I'm pretty golden here.

[Liquidity]

Nice.