Yet another 3 amigos problem, I'm afraid. But at least I've done a little research like reading this forum and RAVE a bit.

Symptom: After 2 days intermittent ("cured" by switching on and off the ignition), the 3 lights are permanently on. I have verified that I can spin a wheel under hard braking, and on a hard right hand turn without the characteristic whirring noise and vibration that we associate with working ABS and Traction Control. HDC just beeps at me, and does nothing as far as I can tell.

The lights are on all the time regardless of vehicle speed.

From posts on this forum, it seems that this can be down to dirt on the abs wheel sensors ? Unfortunately, I had no squeaking brakes, and although I cleaned the wheels and around the hubs, it has not cured the problem.

There is a small pulsing noise from the ABS unit at the top of the passenger side (right hand side looking up the bonnet) of the car. To the best of my knowledge it has always done this.

One possible related factor - the cruise control has stopped working. It started to lose speed on a run a couple of weeks ago (set it to 70 and it would try to maintain 65, then 60, you get the picture). Doubtless it is vaccuum pump related, but the manual says it wont work if a road speed isn't received from SLABS.

Previously the only way I could engage ABS was to brake like crazy when I passed over a wet metal manhole cover at the foot of a hill, which I did rather childishly every so often for kicks. Now with ABS off, the brakes are still strong and it all pulls up nice and straight.

I know a small independent that's pretty good, so I'll take it in to him. But before I do that, I thought I'd ask your learned opinions.

From RAVE there seems to be 4 failures that fit the bill (nothing working and lights on).
The shuttle valve, SLABS ECU, the relay pump or the mysterious "Voltage out of range".

The self levelling suspension controlled by SLABS works, and he vehicle will raise and lower its **** normally.
Pressing the brake pedal when starting has the "whirr and vibration" which I believe means it is testing the relay pump. Dunno if the whirr and vibration means it is working or not though ! It has to be the relay pump I'm feeling because RAVE says if you don't move the vehicle above 4mph, it won't test it again on the next ignition on, and sure enough ...

So, I'm concluding its the shuttle valve and the Cruise control is co-incidental.

Any thoughts ? Any more tests I can do, or anything to look out for ?

Is it safe to drive the vehicle to the garage ? (I never wanted ABS in the first place grr !!).

Do the lights have to be switched off, or will they go off naturally when the problem is resolved ? RAVE seemed a bit unclear on this / I'm thick.

 

Yes it is safe to drive. I think that your cruise and ABS symptoms are sperate issues.
Have him start with the voltage, then clean/test the wheel speed sensors.
Also have him check your front hubs. When the wheel bearings go bad it will throw the ABS sensor(s) out of alignhment.
Let us know what you find so that we may help others.

 

Dave, for more feed back, write one paragraph problems so more of us will spend the time to read it.
Do your brakes pulaste when you brake hard at 30 MPH? Do your brakes squeak?
As for tests, there are none you can do, so answer my questions then go find a small shop that can read your codes and clear them. The odds are with you that if your brakes are still pulsating, your lights may stay off for awhile.

 

FWIW my "permanent" 3 amigos problem went away when I replaced a bad rear hub about a year ago. Since then I occasionally get them but they go away after washing the truck thoroughly, indicating (to me anyway) a dirty abs wheel sensor.

 

Sorry about the formatting ! DiscoMike, today's test shows that it *does* pulstate above 30mph if I aim for a badbit of road repair. On a goodflatroad, I can brake from 50mph with no pulsation. These18" Pirelli Scorpionsgive a lot of grip ... No, the brakes don't squeak, and never have done.Can't test the traction control until next week as I'm scrabbling for an early morning flight.

 

I'm unclear on how the warning lights work: on the one hand they seemed to switch themselves off a couple of days ago, indicating that the fault was intermittent in the same way seemed to happen when Disco 2 SD7 replaced his hub, but on the other hand DiscoMike andother related posts I have readtalk of TestBook required to clear them ?

 

Mine are all on and I am trying to eliminate problems / maint before I go to have the codes reset. I am about to change the front brake pads. How do I clean the wheel speeds sensors while I have the calipers etc off?

 

Just spray them with brake cleaner.

Yes, to read ABS codes the shop needs a special scanner. It has to be a ABS scanner, call around to shops and see who has one. Not many do.