Problem vr6 abs problem

[Wesleyvr6 10]

Good afternoon all, after overhauling the complete brake setup on my C I have now come to bleed the brakes but the abs pump doesn't seem to work when I put the ignition on! I have manually wired up the abs pump and it runs as it should, I have pulled out the 3 relays behind the glovebox and tested them all and they all work fine, one of them clicks when the ignition is turned on, is there anything else I an check as to why the pump doesn't come on? There is no pulse in the pedal now when the ignition is turned on either??

[Wesleyvr6 10]

Is it only one of the 3 relays that is supposed to click when the ignition is switched on?

[RW1 0]

Good afternoon all, after overhauling the complete brake setup on my C I have now come to bleed the brakes but the abs pump doesn't seem to work when I put the ignition on! I have manually wired up the abs pump and it runs as it should, I have pulled out the 3 relays behind the glovebox and tested them all and they all work fine, one of them clicks when the ignition is turned on, is there anything else I an check as to why the pump doesn't come on? There is no pulse in the pedal now when the ignition is turned on either??

 

Pump doesn't run unless the ABS detects a need to. Doesn't usually affect the pedal on start up either. Brakes remain in a latent state, ie. all ABS valves in the ABS block relaxed and the pump off, no pump unless the wheel sensors detect a rotation speed change relative to each other.

 

If you want to know its working. Find a wet surface and brake hard. The pedal will pump then.

 

.

[Roger Blassberg 0]

What is happening in the ABS system when it goes through the "ignition on, light on/off" check? Is it just a check of electrical continuity? And what about that other thing that hapeens at about 10mph after first starting up - a sort of shudder through the car?

 

Best wishes

 

RB

[Tristan H 10]

how does one manually wire up the pump , to make sure it's actually pumping?

[dr_mat 0]

If you want to know it's working, start the car and pull away. When you reach 10kph you'll hear and feel a little graunch through the brakes - that's the self test. As stated above it doesn't *do* anything when you turn the ignition on.

Plus of course if the dash light goes on then off as normal there's a good chance everything's fine.

[Wesleyvr6 10]

Ok thanks for all the replies everyone. Now I have everything on the abs side running I started to bleed the brakes! Me and my friend(Audi mechanic) have tried 4 times now to bleed the brakes! The problem we have is the pedal seems fine after pumping the brakes once, but the next time you come to press the brake they seem to go to the floor! We definitely have no leaks and have pumped at least 1.5 litres through each caliper! We have also bled the abs pump! Where are we going wrong? Everything worked fine before I did the 312 upgrade and new rear mk4 calipers? I know a lot of fluid may have leaked out of the system as we were upgrading everything over a couple of days!