My 2002 XJ8 with 50K miles has now developed the above problem more and more frequently.
The code reader only gives me a P1649 code and none of the ones that relate to ABS sensors or module issues.
Have searched the site high and low and found a lot of information but nothing on this line.
Am at a loss.

 

I would bet on a broken or intermittent wire at one of the wheels. Does it occur while you are turning? I seem to remember Danielsand had this problem when turning right, it was a frayed wire.

 

Not really driving straight a head it can come on. I am not sure but the other day it came on as soon as I started the car without moving. Strange thing is why none of the related error codes?

 

Check your battery, and search the forum on this issue.
These cars are sensitive on their electronics, and a battery which is less then optimal can cause your exact symptoms.
I speak from experience, did not have a single warning after exchanging the battery last year.

 

Thanks, the battery is new and full, but then the check engine light came in.
No code other than the 1649 so I erased it. Took three attempts to do that.
Have driven it for about 20 miles and all is well ???? Will post if anything changes.

 

None of the generic code readers can read C codes which are manufacturer specific
and include the abs system.

You can spend a lot of time searching for the problem, so I suggest you take it to a foreign car specialist who has the necessary software.

 

+1 RJ

 

My XJR used to do that, even on the road on the way home from the sale.

I removed all 4 ABS sensors at the wheels, cleaned them up and the ABS ring on the disc, put it all back together, and after about 200m on the road the light went out.

Try that. I'm sure you can find on the Forum somewhere the instructions as to how to remove the sensors. It was easy.

Lyndon
On the decline toward wine o'clock Sydney time.

 

The "known issues" for the faults you mention are the sensors, the sensor wiring and a FREQUENT problem with failure of the power connector for the ABS pump motor on the ABS controller circuit board., You can only read the ABE module codes with dealer level software or "Auto Enginuity with Jag extensions" to distinguish what your fault is.

Assuming the failure is the power connector, you can either solder it yourself, after sawing the module apart, or cutting a hole in the case with a hole saw, then putting it back together, or paying one of the modukles repair guys to do that, Look to the archives for MANY references on either solution.

As to the error code you are getting. That code means the communication bus token pass has been interrupted. It can either come from a bad bus interface on wone of the modules, or (more likely from your description), from the act of connecting your scanner. Does your CEL light come on AFTER you are connecting the scanner?

 

Thank you all, having used the scanner that I have and getting error codes on other XJ8's that I have made me assume it could read the ABS one's as well.
Currently all is well but will follow the course of cleaning the sensors, checking the wiring and lastly making sure the module power connector joint is well.

 

My 99 still has these messages so I'm planning on looking into the "solder fix" detailed fairly well on this bb but when I first started looking into this issue I found this diagram, referred by another member, very helpful...
http://jagrepair.com/images/AutoRepa...heet%20XK8.pdf
It allowed me to leave the car on the ground with the wheels in place and check to see if the old girl was getting the right readings from the wheel sensors, among other things. I'll still be cleaning the tone wheels this spring when the wheels are off for new shocks but they were apparently not the issue on my car.