ABS Pump Failure
 

I recently replaced the shuttle valve on my 2004 Discovery because some one had do the wiring trick on the ABS and I kept sliding around on locked brakes anytime I pressed them. After putting a new valve the brakes felt way better and never locked up. But the three amigos popped up so I went to have them checked and I got the Pump Failure 1 (monitor line) & 3 (pump sticking) as well as the shuttle valve switch failure. The shop told me I needed a new pump and I grabbed my keys and headed out after the quote. Ive been roaming the forum sites for answers but theres not any clear ones. Anyone have some straight forward suggestions or solutions? Cheers!

P.S. could I have not plugged the shuttle valve plug in all the way to bring up all these codes? just a thought

ABS pump failure is extremely rare on these trucks. I've actually never heard of one single case. These trucks electronics are very sensitive. Id try just reseting the light and driving it awhile a few times before I threw anymore money at it. Sometimes just doing a repair will trigger a warning light on these trucks. Make sure the brake fluid level is right. Just putting the shuttle valve on nice and tight should make a good connection, so I doubt it that.

Shuttle valve wiring fix should NOT have caused anything to lock up. Maybe they did something wrong? What color wire did they tap into?

they cut into the green and yellow wire for the wiring job. since ive gotten the disco back from the shop the lights have turned off for the first time but have popped back up under braking and have gone back away after restarting the truck. could it be a bad connection somewhere? i may try flushing the fluid and putting new fluid in to see if that helps

I used to get the 3 amigos after a hard bump in the road or when the brakes squealed, even after I did the A fix and B fix in the modulator.

So if the modulator is ok then have a good look at your four wheel hubs, clean the dust shields, remove rust lumps between hub and shield if there are any, clean and grease the slide pins with the correct grease, and make sure the brakes pads don't squeal. I bet you won't see the 3 amigos again. It took me a few tries to get it right though, but now I am 3 amigos free...

I'd come up with some way to read the codes. Anything else is just guessing. Sometimes educated guesses, but guesses none the less. :)

X1 it may not be the shuttle valves but the internal electrical connection at fault. Mod B should sort this but there are better solutions to the internal electrical issue. The 3 Amigos or modulator mods should never cause inadvertent lockups but lack of ABS and a heavy right boot may on gravel, ice or wet roads. Also no TC if the Amigos are lit and showing. Bearing in mind ABS is not a panacea for all sudden or aggressive braking but merely reduces the lockup risks and gives an opportunity to steer during hard (ish) braking. If you are turning and stamp on the brakes during the manoeuvre the ABS will not save the truck breaking away or skidding. ABS is a driving aid not a total solution.

Lots of reading here about shuttle valves and modulators.

https://www.google.fr/search?q=disco...m=122&ie=UTF-8

Worth a chat with these guys, they almost speak the same language ;) and should be able to help. :)

Land Rover page | Falconworks' Quality Auto Repair | Jaguar, Alfa Romeo, MG, Lotus, Triumph, Austin Healey

The codes that the shop gave me was pump failer 1 & 3 and shuttle valve switch failure he said there were no codes. Also he couldn't clear the lights when I picked it up but they turned off when I got up the next day. I'm going to clean everything this weekend and get new fluid in the system see if that works. Anything else I should throw into the mix to help out?

Also would buying a used abs modulator offline be a bad idea if nothing works? Or is that just asking for the same kind of problems? Thanks

A lot of the abs faults can be intermittent. I'd just worry about whichever codes come back if they come back.

The problem with buying another modulator online is it's a gamble, you may be exchanging your particular set of problems for another equally as perplexing. IMO the best way forward is to have the ABS codes read and recorded properly and where possible work through them and act upon them. A modulator isn't anywhere near as complicated as many imagine but there are weaknesses and repetitive defects as with any engineered contraption. Obviously it's extremely difficult to assess the provenance of any LR modulator for sale online as it could be between 11 to 17 years old and 50K-200K miles of use and abuse. IMO stick with what you have as at least you know the global issues pending and you maybe can sort them. I haven't any idea how much a specialist ABS workshop would charge to identify your particular issues and rectify them but I suppose a call to Falconworks wouldn't be a waste of time.

Thanks for all the responses. I'm dropping the beauty off to get its headgaskets fixed today so I can step away from the Christmas tree dashboard. it stays off a majority of the time now but randomly turns on even without braking. So I'm thinking it's a bad connection somewhere

So is the headlights dimming when the abs pump runs a big hint at a electrical problem? When the abs pump runs when the brakes are slipping on ice or traction kicks in the headlights flicker and dim. Any ideas if this gives a better idea of the problem ?

You need to make sure the ground wire for the ABS pump is good. Locate where they installed it, make sure it is tight. If there is paint or dirt underneath it, take some sandpaper and get to bare metal. Then tighten the ground.

or your pump is failing the the dimming is from the extra amps the pump is pulling.

Pretty common, especially in rust prone areas. Check behind the drivers side headlamp for a bundle of ground wires. They are kind of hard to get to.