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My ABS light has been on for a few years now, never really paid any attention to it UNTIL......the TC light just came on.

So reading in my hardbound factory manual, the section on ABS says the light only comes on when the ABS pressure is low, but also says it can be triggered by an excessive air gap at a wheel sensor.

There is also a procedure to test the precharge pressure of the accumulator, which I'd LOVE to do because it looks so easy, with the right guage setup. Is this guage and attachment banjo-bolt fitting something I could make up myself with stuff from Harbor freight?

Also, the manual says the ABS ECU may record fault codes, or the faults can be determined using the "blink test". Would these codes be displayed on the little digital readout under the passenger's seat, and what is this blink test?

As I said, my ABS has been on forever, and I assumed it was because of bad air gaps or sensors at the wheels. But lately the pump has been noisy at cold start-up, but quiets down after that and seems normal; turns on, shuts off. Braking is NOT WHAT IT USED TO BE, but I also assumed that was because of wrong type front pads.

If my accumulator had a very low precharge, would this contribute to poor braking? If I read the manual correctly, the ABS pump is pumping the accumulator up to ~2800 PSI, so I guess regardless of the precharge pressure, if the ABS switch sees 2800 PSI it will shut off. That's what I'm thinking anyway, I think my accumulator is weak, and wheel sensor airgaps are bad.

Thoughts?
 

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1995-2002 Range Rover P38A
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Regarding the TC light I would be looking at the valves in the ETC Power Block it is common for them to give issue..
Also worth noting the ABS is a rather important system and it shouldn't be ignored, especially if it has crap brakes..

On the UK spec classics, under the passenger side seat "your drivers seat" there is the Wabco CU for the traction control and abs, on the side should be a row of relays, the first one IIRc is a Blue relay it controls the idiot lights on the dash, remove it and check the contacts, it is a known issue for them to fail/corrode.

Also under the same seat you're looking for a stray Blue plug, it usually is easy to find.. wires are coded - White/Pink - Black - Green/Black - Black/Pink You need to bridge 2 of those pins the Black/Pink and the Black terminals, use a paper clip or a chunk of wire.

Once they're bridged, turn the ignition on "position II" the light should disappear, if it does this shows the start of the blink cycle.

There is a "start up code phase" which is.. .

"pause" for 2.5 seconds,
"flash" for 2.5 seconds
Pause for 2.5
Flash for 0.5 seconds.

After this you're into the flash code sequence.

It'll show a "long blip of the light" and a "short blip" once this is done you will get the code..

It flashes in an odd way, i'll try to explain..

FOR EXAMPLE - The light could flash 2 times in succession so that's 2 after a pause usually a second or so it could flash 3 times in succession..

so this would be error code "2-3"


-

Shooting in the dark, it could be the ABS pressure switch..

The RRC manual explains it better above is from memory!!

The manual will also have the code sheet the wabco can produce.

HTH
 

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Regarding the TC light I would be looking at the valves in the ETC Power Block it is common for them to give issue..
Also worth noting the ABS is a rather important system and it shouldn't be ignored, especially if it has crap brakes..

On the UK spec classics, under the passenger side seat "your drivers seat" there is the Wabco CU for the traction control and abs, on the side should be a row of relays, the first one IIRc is a Blue relay it controls the idiot lights on the dash, remove it and check the contacts, it is a known issue for them to fail/corrode.

Also under the same seat you're looking for a stray Blue plug, it usually is easy to find.. wires are coded - White/Pink - Black - Green/Black - Black/Pink You need to bridge 2 of those pins the Black/Pink and the Black terminals, use a paper clip or a chunk of wire.

Once they're bridged, turn the ignition on "position II" the light should disappear, if it does this shows the start of the blink cycle.

There is a "start up code phase" which is.. .

"pause" for 2.5 seconds,
"flash" for 2.5 seconds
Pause for 2.5
Flash for 0.5 seconds.

After this you're into the flash code sequence.

It'll show a "long blip of the light" and a "short blip" once this is done you will get the code..

It flashes in an odd way, i'll try to explain..

FOR EXAMPLE - The light could flash 2 times in succession so that's 2 after a pause usually a second or so it could flash 3 times in succession..

so this would be error code "2-3"


-

Shooting in the dark, it could be the ABS pressure switch..

The RRC manual explains it better above is from memory!!

The manual will also have the code sheet the wabco can produce.

HTH
This is good stuff...
I have never seen this information ..,
I am going to have a look..
 
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