I have purged nearly all of the electrical gremlins in my 90 XJS but I still have one issue...the ABS light on the dash.

I have cleaned every connector, gone through the dash and replaced the accumulator but the warning light remains.

The ABS pump is working fine. I can hear it and see it wiggle when it kicks on. Also, I just bled the brakes and the pump worked fine to pump fluid the the rear brakes.

Anyone know how to test the wheel sensors? Any other switches or relays I can test?

Thanks!

Mark

 

Accessing ABS codes

 

I'm not sure if that will work for my '90 but I will give it a try. Do you have the section where it explains how to clear the codes and reset the ABS ECU?

Thank you!

Mark

 

look

 

Thanks again!
Mark

 

All years with teves ABS is the same

 

You have been very helpful that I hate to ask for more...but...if you dont mind could you please post the ABS Error Codes?

Thanks!

Mark

 

https://www.jaguarforums.com/forum/a...es-mark-ii.pdf


Here you can see the whole document.

 

Some good progress today. The information provided above allowed me to get the fault codes.

The only code so far is a #32 - Right Front Wheel Sensor.

I did not have time to get under the car today but I will do that this weekend. Hopefully it will just be a dirty connector. These sensor look like simple coils so I should be able to measure the ohms and compare it to a good sensor.

I will report my findings as soon as I have them.

Mark

 

I suspect it's not a connector, for the wire is prone to get hard from the heat and split.
Removing the tire and you will see.

 

Hi when abs first appeared on "normal " cars and diagnostic equipment wasn't available to meer mortals we often found that the fault was on the front sensors due to the constant movement of the steering. To test we probed the multiplugs on each wheel ,spun them up ,got a reading on each and then compared them, any reading that was way out with the others often proved to be the faulty one. Hope this still applies good hunting .

 

These are the same as the speed "sensors" on the engine of a Marelli car. They don't sense anything. They produce a AC electrical voltage. Either the wire has gone bad, or the magnet has surpassed it parameters of being able to create the field needed to stay in the tables set in the ABS ECU. I have told anybody who will listen, that in my opinion, checking the clearance of these "sensors" is a must on the engine. Closing the gap is as simple as filing the mounting boss. Not so easy on the wheel units. I bet though, if the wire is bad, rebuilding one with a new wire wouldn't be too bad a chore, given some heat shrink, time, and the right coax.

 

I put a meter on both front sensors today. The left one measured 1.076K ohms and the right one measured 1.058 ohms. Seems to me they are ok.

So either the signal from the right sensor is not making it back to the ECU or the ECU itself is bad.

I'm going to swap the ECU and see if that fixes the problem. If not I will go through the wire harness.

Stay tuned!

Mark

 

My ABS light would come on, and I missed it when I bought the car (96 XJS). Found the front left sensor was gunked up with anti seize when someone changed a wheel bearing. I was able to remove the sensor and clean it, then I was able the clean sending disc through an inspection hole in the dust cover. Up and down the driveway the light would still come on, it took a good 20 Kilometers on the road to clear. Problem solved.
Snowball