<E28> HELP! OBC gone nuts!!

[Dave Imme <dimme@xxxxxxxxxxxxxx>]

In the past few weeks the OBC in my 88 528e has started losing the date,
time, and range setting after a restart, plus the tempature wa going
crazy (fluctuating like crazy).  Then the last few days it seemed to be
ok.  This morning, while I was a clients office doing some work and
about to leave, my employee (I'm deaf, he's not) could hear some alarm
going off and then realized it was my car.   In the 2 years I've had it,
I've never heard nor set the alarm (much less knew I had one, really).
The OBC mph limit light was blinking, the alarm blaring, I started it,
it stopped, started again...looked at the owners manual to shut alarm
and followed that procedure a few times before it would stop for good.
After getting it going, setting the OBC (date, gime, etc) it would be
fine, til I shut it off.  When I go back to drive the car, the OBC would
lose all its settings.

Why?  Does the OBC run on its own batteries?  I did change the batteries
before in my instrument cluster, but saw no reference to the OBC.
Someone please shine some light on this.

TIA

Dave Imme
88 528e (needs prozac)

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