Hi
I posted in aoither thread but thought I would start my own one as conclusion may be a help to others.

Car is 1998 UK XJ8 Daimler LWB

Anyway heres they story so far

I have abs traction control and stability control light / message on constantly
Car has sat up for a year with no warning lights when parked up
Put good battery in it
Measures 12.5 volts drops to 10.6 under load and 13.8 while running . I cleaned and checked resistence on all 4 wheel sensors values were 1.083 1.1 on front two and 1.057 and 1.064 on rear ones
I then went to check the abs harness plug for resistance and got 1.035 and 1.055 on front and 1.035 and 1.040 on rear.
The pump plug directly below the abd harness gave reading of 4 ohms.
Just hooked up code reader and got the followinf codes
C1155 Speed Wheel Sensor LF Input Circuit Failure
C1233 Speed Wheel LF Input Signal Missing
C1145 Speed Wheel Sensor RF Input Circuit Failure
C1234 Speed Wheel RF Input Signal Missing

I pulled out the ABS module and opened it up, the solders looked fine but I resoldered anyway just in case , see pic below just opened up


I put it back together holding out little hope and no differnece

I then checked voltage at front sensors on the white plugs
Got reading of 2.32, is this way off the mark?
I checked harness for continuity which was fine and then checked for voltage at sensor end also and got 2.32

Since the codes i pulled only indicated front problems I checked voltage on rear sensor harness and also got 2.32

Have also checked the fuses and all are good.

I have hit a wall with this, am trying to get car sorted for its MOT and if I dont get it sorted Ill end up breaking the car for parts.

Anyone any help?

 

is it on constantly or just from time to time?

 

Constantly on, if i do a hard reset and restart car i just get ABS light on constantly but as soon as i turn the steering wheel a small bit Stability and Traction control warnings illuminate and remain on constant there after

 

You do not have a C1095 code, so the connection to the pump is probably okay. But I don't think the picture of the pins shows a good enough solder repair. It is often necessary to scrape the insulation away to get a good flow to the circuit board.

I had a module with a circuit board fault that gave open circuit codes. I replaced the module. Your wheel sensor resistance readings are good, but there is always the possibility that both front cables have breaks that only show when you turn the steering wheel.

I assume you are driving the car. ABS codes will often not go away unless the car is moving.

 

You seem to have checked all the electrical connections.
Sometimes the wires to the front senders can break, causing intermittent problems. Suggest checking for continuity while flexing the cables.

 

Hi RJ
Thanks for your input, one important point you hit on is that I am not driving the car, it is sat on the driveway, no insurance or MOT on it.
As you say maybe the car needs a good run out as it has sat up for over a year
I should have posted other pics of module repair, the one in first thread is before repair, the solders looked OK, i just went ahead and soldered since I had it open and is known as a weak point.
I am also going to change the brake fluid also, car needs it anyway.
Heres pic of repair, I used a bicycle patch to cover opening, will see how it stands out but seems as if it will be up to the job.

Fredd, I had done what you said about wriggling the wires around on both front cables and had no continuity problem, Its starnge that both would just go together anyway as the car has been sat where it is/not driven and had no problems before been parked up.
A good blow down the motorway is in order I think.

 

It sounds like what you need to do is get the car moving, and see if the codes reset. I usually takes only a few minutes for the ECU to cycle through the internal tests and reset.

 

Right, I have just taken car out for a run and just as I started it up i noticed the speedo needle jumping up and down slightly, went out the road and discovered speedo isnt working now or either is cruise control, I did take the car for a run last week and both were working then
Have I knocked out the speed sensor distance to speed sensor ring maybe?
Is there a specific wheel sensor which measures the speed for the tacho?
Thanks

 

Yes I believe the ABS controller goes through a system check at about 20mph. If you have had faults, and presuming the system is fixed, they might not clear until the next time you pass through that speed. That was my experience on the XJ8.

If the system is still faulty, my suggestion would be to use one of the by-mail repair services. I got sick of messing about with my Discovery's ABS. Sent the ABS module off, paid $175, got it back repaired, tested, and guaranteed. No more problems.

 

This is getting even stranger, i just checked again the resistence on the ABS module plug on the 4 sensors
The only one I can get resistence on now is the Rear right (which measures for speedo I believe)
So now I seem to have a newly developed fault on the other 3 sensors which all measured good the other day.

 

I had the same light about 3 months after I bought mine. While I had the hood off for timing replacement, I pulled the module and shipped it off to Tenn. for the repairs. It was super cheap, was returned looking OEM (FedEX out and back in less than a week). When I got it back it came with lifetime warranty on repairs, and a note of about HALF A DOZEN repairs that were done on the board. The power points are not the only ones known to fail but they are the ones that get most of the press. Just something to think about, you might have done a great job soldering the power pins but it's worthless if there are other points that have failed.

 

Yes but now I seem to have a fault on 3 sensors between the abs plug and the wheel sensors

 

I'm pretty sure it's left rear for speedo. Are you measuring resistance from the multipin plug that connects to the module?

 

Yes rj as per previous thread about which pins to measure
It's really baffling that I got good readings before I did abs module repair
And now after reconnecting everything I can only get reading on the rear right sensor

 

First thing I would do is take the big connector off the ABS-unit and clean all the contacts, either in the connector as well as in the module.

Then a question I got to everybody here, does the XJ8 have a steering angle sensor? Normally that works together with the ABS-ESP system, if that one is out of order or needs recalibrating you got the same problems.

I just got this thougth when I read in your openings post the error comes up when you turn the steeringwheel.

Anybody knows about the steering angle sensor being present in an XJ8?

 

Nick, I think that's in the newer models.