ABS Pump Keeps Running

[Range01]

I have a 2001 P38 4.6 which has been off the road for 5 months during a motor rebuild. That's all good what I trying to work now is why the ABS Pump keeps running. It was fine before I took it off the road.

This is what I have done so far:
New Battery
Changed over the pump and pressure switch
Recent new accumulator (six months old)
New brake fluid and system bleed last week and good brakes - no air in the system
Tried a different fuse box and relay.

What happening is the ABS relay is getting a small voltage not enough to light up a test light but enough to hold the relay on. I have taken off the black relay cover and re inserted it into the fuse box when I turn the ignition on it will power the relay and the ABS pump I can then hear the pressure switch click which should turn off the relay however it stays on. I can apply a small amount of pressure to the contact and the relay will switch off. I can't manually open the relay whilst the pressure is building as the voltage is 12 volt.

I hope I have made sense I do need some help.

Could it be the ABS ECU under the glove box if I unplug the middle plug the relay doesn't get power.

Cheers

John.

[finallyrangie]

When mine did the same thing it turned out to be the relay giving up, I see you have tried a different relay and fuse box, were they together, if the relay has overheated and started damaging the circuit board in the fuse box you might have a self perpetuating problem unless you replace them both together.

Otherwise you do seem to have tried most options and it might be the computer is the only thing left.

Good luck and keep us posted

[Range01]

I have a new fuse box on order I will also purchase a new relay. I have just spent a fair bit money on her and plan to kept her another 5 years. What I thought was a head gasket ended up as slip sleeve so after stepped sleeves new rings and bearings rockers the motor is like new. (all done in my garage except the machine work which was done at by Paul at Gown Hindhaugh Box Hill Vic) Her main use is to tow our 3 + ton boat which she does well. I will let you know how I go - I have taken her to my local land rover workshop and they did give me plenty of advice and are still helping.

[Range01]

Purchased a 2nd hand ABS ECU plug it in and it fixed the problem. Also put in a new fuse box as a precaution expensive but will make it more reliable.

[finallyrangie]

I did the same thing with my fuse box, worth it for the peace of mind, I read on here somewhere that changing it every five years was a good idea, if it works I will.