Some OBC functions not working

[SharkInfested]

Well I tucked the "kids" in for the winter I started thinking about an annoyance on my 88 M6.

The speed and fuel related functions on the OBC don't work (ie AVG MPH, M MPH, AVG MPG and Range).

When I bought it two years ago, I noticed hairline fractures in the dash cluster plastic which could have resulted in the cluster being hastily pulled at one point.

Question is, could there be connections that were forgotten to be plugged back in preventing the OBC from getting fuel and speed data?

I have already replaced the OBC and its computer and they weren't the problem. Side note: the cruise control doesn't work either, leading me to believe it was non re-plugged wires behind the cluster.

Thoughts? Thanks.

[ozibimmer]

HI there
Your problem sounds exactly like my car did a year ago.
I bet the Blue small L type plug for the Cruise control has come off the back of the cluster. Its the one for the cruise control and sits behind the speedo dial on the left side of the cluster. It just clips in and with out it all you mentioned above will not work.
Here is my DIY for Dash removal and shows how to get the cluster out.
Hope I this helps you helped you
http://bigcoupe.com/phpBB2/viewtopic.php?t=20630
You can see the Blue plug in the below pictures surrounded by the green line.
Regards
Addam

[SharkInfested]

Addam,


Thank you for so confidently responding to my post. I'll likely take up the project in the spring it's in offsite storage.

It'll be a while before I give you an update, but I will when the project is complete.

Best,
Sam

[emccallum]

I know this is a very old thread but I came across it searching for my OBC issue which is the same as the original poster.

Big thanks to ozibimmer, as I examined my connectors on the speedometer and found someone had plugged the blue plug into the wrong terminal. Cruise and OBC both fixed! I was able to access the plugs without removing the cluster. Thanks!