BMW E31 OBC/MID mod

BMW E31 OBC/MID mod to display oil temperature, oil pressure and battery voltage - work in progress by martin from www.8er.org . Currently the project is stalled, but once completed Martin intends to sell it as a kit for E31 owners.

Category:

Autos & Vehicles

Tags:

• BMW
• E31
• OBC
• MID
• oil
• temperature
• pressure
• voltage
• 850
• 850i
• 850Ci
• 850CSi
• 840
• 840i
• 840Ci

[BMWg84]

That looks great. Too bad so many of these E31 MIDs lose their pixel displays and they are impossible to find used at a junkyard. I had good luck with GermanAudioTech on ebay who repairs them. Saved me hundreds of dollars.. Also, do you know which wire is for the IBUS? I am wondering if you can put the E31 OBC into an E36?

[reyan00]

@BMWg84 - The E31 MID will not work in the E36. Unlike the E36 MID, the E31 MID is just a dumb device that displays whatever comes in on the Ibus. All calculations are performed by the car's EKM module. If you press a button on the MID, the EKM takes action and puts whatever needs to be displayed on the bus. The E36 MID does all this by itself. Also, I'm told the E31 uses an early version of Ibus with incompatible identifier strings.

[1D0N]

@reyan00 What about using an E36 OBC in the E31? Although of course you'd loose the Service Indicator.

Do you know if the E36 OBC has an iBUS imput? I now use my CD43 as a display as the E36 Kombi doesn't have a MID in it. CD43 is limited to 10 characters, while the OBC could display...well didn't count, but must be at least 20.

[reyan00]

@1D0N - Even if the E36 MID could read the Ibus, it would not work properly in the E31. The E31 was the first BMW vehicle with Ibus and it's more or less a prototype version. The E31 Ibus protocol is incompatible with later versions.

[mrgismoman]

Yo, I have a 1993 e31 bmw 850 5.0 v12 and wondered if you know how i can do the instrument clucter check because all my dials have stopped working but still have a few lights working on the dash. Thanks

[reyan00]

Instrument cluster test:

1. Turn ignition off

2. Press and hold trip/odometer reset button

3. While holding reset button, turn ignition key to first position

4. Enjoy the show...

I'm an 8 series driver, not a mechanic. If you have questions, register for an account at 8er(dot)org (free). Lots of 8 series owners there and a lot of knowledge.

[1D0N]

Did this project ever continue?

[reyan00]

@BMWg84 - I already replied in detail to your mail, but basically the EKM is the electronic brain of the BMW E31. It's the module that drives the instrument cluster and MID and controls various functions of the car.

[GeezaHD]

@BMWg84 Fix it yourself, google how