ABS Problem, <E30>

["Fernando C. Lebron" <lebron@xxxxxxxxxxxxx>]

Hello BMW experts,
 
I am writing to ask for your help. 
A couple of days ago, my daughter borrowed my '88 325i. She had a little
problem starting it, exhausted the battery and asked a friend for help.
They used booster cables and got it going. When she came home she told me
what happened and I did not think too much about it. But next morning, the
ABS light in the dash was lit up and remained lit up. Then I tried braking
hard to see if the ABS was working and I found out that it was not.
Everything else works fine.
My questions are: 
- - Is this a common problem? 
- - Is there a solution (short of taking the car to a dealer)? 

I know quite a bit of electronics so if someone could point in the right
direction I would appreciate it.

Thanks. 

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  Fernando C. Lebron, P.Eng.
  London Health Sciences Centre
  London, Ontario, Canada
  E-mail: lebron@domain.elided

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