Laurence Gibbs

Fault: At start up , ABS light comes on along with gong and light stays on while all others go out. Previously the ABS light and gong came on for a short while and went out and all was well there after.
So far i have.....
tested R34 ABS relay. pin 30 supply to ABS brain 13v when engine running, pin 31 IS grounded less than 1 ohm. Pin 15 is 13v when engine running, pin 87 13v. I have also tried strapping out the relay just in case a h/r exisits. So i think the relay is all ok.
Pin 1 of the ABS brain is 13v when engine running connector un connected. All the solenoid valves read about 4 ohms at the ABS brain connector taken wrt to pin 20 gnd for solenoid valves. All wheel speed sensors read 1k ohm apprx.

I am making the assumption that the pin outs for the RS brain are exactly the same as a C2 ABS brain.

So not sure where to go from here? Any help , ideas welcome. Is the abs unit known to suffer h/r 's ?

Laurence Gibbs

Boost pump works fine. Hydraulics light goes on at start up and turns off 20 - 30 on first start up . quicker on subsequent start up , fuse 15 ok (has to be for pump to run).
Not tried latching the brain connector in the way you describe steve, got to be worth a go.