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E28 OBC question (where is it!)

My OBC ('85 UK M535i) has been showing PPPP since I bought the car, time and date fns work OK but nothing else.

I'm really struggling to find the relay box for the OBC. I can find the bonger and there's a space next to it in the rack under the steering wheel that I suspect is for the module.

There's a space under it which has the UK/euro alarm (the one that needs a second door keyhole for the magnetic key!), I initially thought it was the relay module until I realised it had too many connectors.

Have tried tracing the wiring but to no avail as yet. I suspect the unit is missing completely.

Can anyone tel me where it should be, even those with left hand drive cars!

Reply to
John Burns
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A thought, I wonder if cars fitted with the BMW alarm had a modified OBC relay box which combined the functions of the alarm and OBC? The OBC box has blanks for other connectors and looks SO similar to the alarm box.

Reply to
John Burns

Turned out to be a dead display module, which is the first dead one I've seen! There ARE to types of relay box, one for normal cars and one for those with the factory alarm.

Reply to
John Burns

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And there you have it... mine doesn't have the factory alarm. If a working display is needed, I may be able to help. We have a few here (Omaha, NE). Are you sure it's not just a dead lamp? With the key "ON", you can see the working/unlit display with a flashlight (torch). I also have the light module, which slides into the OBC from the side. Just saying for the sake of the uninitiated reader, since I'm sure you already knew this.

Bill in Omaha '86 535i (without factory alarm)

Reply to
Bill

Lamp was fine, symptom was PPPP on a few of the functions. Most of the online sources seem to say it's a bad relay box, so I was surprised when I had to change the display unit.

Reply to
John Burns

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