ABS Relay

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Kemlo
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Joined: Tue Sep 25, 2007 11:00 pm
Location: Birstall, West Yorkshire

Post Wed May 08, 2013 12:49 pm

Fried my ABS relay jump starting the car. Went to stealers to get a replacement to find they are listed as NLA and no replacement part is listed as superseding it...

I managed to locate a working second hand one (Christ it was expensive!!!) so I'm all good for now, but given how important that relay is I'm surprised it's NLA.

Anyone shed any light on a replacement for future reference?
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Brianmoooore
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Post Wed May 08, 2013 1:25 pm

It was only used in earlier cars - up to around '89. Later models received their power from the engine DME relay, via pin 20 of the C101 engine plug, and dispensed with the over voltage protection part of the circuit completely. Whether there is any difference it later ABS ECUs that makes them resistant to voltage surges, or whether it was just found that the potential problem didn't exist, I don't know.
I would consider it acceptable to repair a faulty relay (assuming the zener diode hasn't blown) with a 8 amp fast blow fuse, which can be fitted inside the case or in line externally.