OBC gone partly mad!

[john <j.s.smith@xxxxxxxxxxxx>]

The OBC on my '89 325i has, this morning, started to do this...

- -Turn ign on. OBC Displays dashes (as usual)
- -Enter the security code and start engine
- -The dashes, which should change to the time-of-day, just stay there!
- -Pressing the button to change to date has no effect, dashes still there
- -ALL other fucntion work perfectly ok and the dashes get replaced by
sensible display
- -Pressing Time button again brings the dashes back again

We had a *sudden* very cold temp drop in the weather last night - things
have warmed up this morning but the OBC is still - mad! Any ideas what
wrong here chaps?

TIA

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