ABS not working

My car has ABS but it doesn't seem to be working. The fluid is new and has been flushed through and bled twice, the white ABS relay has been checked and is working, the rings have been cleaned and the light is not on on the dash. The brakes work really well otherwise with great power and feel.

Any ideas?

Cheers

Jon

[phildini]

Seized ABS motor? moisture gets into it and stops the motor from doing it's thing. Also are you sure the bulb works on your car?

Bulb is working and goes on and off if you remove the relay (you can feel the relay kick in whilst you are doing this).

Am I right in thinking the ABS unit is fairly common and used on other cars? Anyone have a part number I could chase?

[BIG_MVS]

Bulb is working and goes on and off if you remove the relay (you can feel the relay kick in whilst you are doing this).

Not sure I understand? So with the relay in the light does not come on or off?

Could be anything, ECU, pump a sensor...?

I do have a complete ABS package from a breaker (pump, driveshafts, ecu and wiring and sensors) if it helps?

With relay in the light goes out and stays off. Presumably that means the ecu (tried two in there same result) can read all the peramters it needs to and is therefore not showing a fault. If this is the case then pump might be suspect as its not delivering ecu instructions.

Or am I being a thick muso!

[stephendell]

You really have to stamp on the pedal and lock it up big stylee in a GTA to get the ABS to work. Have you tried hard enough?

[mettersl]

Jon,
when you turn the ignition on, the abs lamp comes on, and then turns off a few seconds later after the self test?
Can you hear the relays operate within the abs unit (you should hear a self test sequence?) they are under the black plastic cover with abs on it on top of the modulator and plug in.
The motor should also start briefly (put your sensitive musicians ear to it).
There are only three other valves that then operate to check. This means taking the ecu off and bridging contacts and listening for them.

I have a copy of the GTA abs supplement, this has fault finding charts in it. If you get stuck I can scan it or photocopy it and send it to you.

The abs modulator can be rebuilt by a diminishing number of people, BBA- reman can do it but there are others. Expect a £200 or so bill.

http://www.bba-reman.com/catalogue/Product.aspx?product=2225
Lee

[mettersl]

More choices
http://bmrecon.com/abscontrolunits.html

or
http://www.ecutesting.com/bosch_abs_pumps___modules.html

The bosch number is on 0 265 100 010 (according to BBA), its stamped on it.

Lee

You really have to stamp on the pedal and lock it up big stylee in a GTA to get the ABS to work. Have you tried hard enough?

The brakes work really well, they've only locked up when i tried to make them do it in the wet but this was under severe provocation. At this point the pedal didn't pulse and the front wheels just locked.

The ABS lamp goes off almost immediately after start up. I'll have a listen to the modulator at the weekend and see if it's starting up.

Thanks for all your help!

Cheers

Jon

The bosch number is on 0 265 100 010 (according to BBA), its stamped on it.

Lee

Just looked up this part number and it seems to be the ABS ECU- any ideas on the modulator? Even the Renault part number?

I was advised to try braking on damp grass, if you can and the ABS is working then it will kick in on wet grass.

[mettersl]

I'll go and look in the morning, but Jon I'd call these people and see what they say, from what you describe it could be ecu or modulator at fault.
The modulator is pretty standard the ecu alp only as I understand it software differences Innit....
Cheers
Lee