P38 ABS woes!

Greetings from an unusually dry day by the river Clyde!

I'm a P38 newbie and need some help please. Car is a YR2000 4.0 with just 48,000 miles on the clock.

We've owned for just six months and it's spent most of that time 'off the road' in various garages having firstly the HEVAC and then the EAS fixed - now it's the ABS's turn to play up!

Symptoms are that the ABS pump runs all the time (even just on ignition) and the ABS warning comes on the dash after half a mile or so. The brakes are otherwise working just fine (not sure about ABS - need a brave local moggie to do a mad dash across the road).

So far, we have...
- checked brake fluid level - fine!
- checked all ABS fuses - fine!
- replaced the ABS (black) relay in the fuse box - no difference!
- local garage diagnostics advise... 'pump is running all the time'
- fitted new accumulator - no difference!
- changed pressure switch - no difference!

We know that the pump runs 'cos the brakes work fine, but don't know if it's producing enough pressure to charge the accumulator and operate the pressure switch. The pump does get very hot - quickly!

Is there a test procedure for the pump/ ABS circuit which would help us decide what to do next?

Where is the ABS ECU?

Any help and advice very gratefully recieved - thanks!

Andy.

Hi Andy, you need to download a copy of RAVE. Page 789 give a diagram of the abs component locations. Number 2 on the diagram is the ecu. Hope this helps
Bill

Hi Bill

Thanks for that - on the case! I'll see if I can make any sense of it. Never been to a 'RAVE' before!

Will someone tell Maclaren that cars need fuel and wheels to win races!!!

Andy

Do you know where to download RAVE? You could do a lot worse than asking datatek to make you an EAS cable. He will send you a disk with it including the rsw air suspension software and rave. He is one of the more knowledgable characters on this forum.

You really need to get the system tested with textbook or other diag kit to show what is happening
Quick check is the pump relay in the fuse box do stick on and th pump failing

Hi and thanks for the response.
Yes, I think more diagnostics are a good idea.
Have already changed the pump relay.
Andy.