Hi all,
i request any help or advice that people can provide.
My problem child low km 1997 4.0lt XK8 has thrown up a Low Brake Fluid Warning Light.
The car should be the flagship of our little fleet of Jags including our wonderful and hard working XJ300 and Daimler Double Six but in fact suffers a continual string of problems mostly associated with the computers. It seems rare not to have some dire message being announced.
Recently it was in Melbourne having it's traction control mechanism replaced. Shortly afterwards it threw up the Low Brake Fluid Warning. The fluid level is fine. I checked the connections at the reservoir, also appears fine. Unplugged the wires, no change, bridged the the two wires, no change, disconnected the battery in the hope it might reboot, the warning stubbornly remains illuminated.
I spoke to Jagdaim who could only advise replacing the entire reservoir at a stupendous cost of around a grand.
I am totally unconvinced this would solve the problem, I believe it more likely a computer glitch.
Has anyone experienced this problem also?
Can anyone tell me if the fluid level sender in the reservoir is anything more than just a float switch?
Can anyone tell me what resistance I should measure on the terminals of the reservoir.
This problem is so frustrating. Driving a car with a red light on the dash illuminated somehow destroys the pleasure of this otherwise great car.
What is most frustrating is that in almost all ways the XK is a great car. It always seems to have just one more little fault to iron out and then it will fine. 420 thousand km in the XJ 300 and never a light to be seen. On fixing a problem with the XK and a trip to town seems to bring a new and unexpected warning.
All advise greatly received
Al

 

Al

Bad news is that the Brake Fluid level sensor is integral to the tank and it’s very expensive to buy new. Good news is that that may not be the problem.

Good practise is to clean the sensor wire connection at the tank and also the large connector at the ABS module. Some members have reported that doing the DIY ABS module solder fix on the PCB power pins also resolved this problem.

I had a lot of strange warning messages when I first ran my 1999 XK8. Seems like if the battery drops below 9V at start up, there’s not enough power to drive the electrics in the car and it throws a lot of false warnings. For me, the warning signs are the windows memory fails, ABS/Traction control warnings and the Low Brake Fluid warning.

Generally the X100 is very sensitive to battery charge. For a lot of owners, it’s an occasional drive so they put on a CTEK battery charger/minder when the car is not in use.

Get the battery load tested at a professional garage and they should show the voltage at start up. Also check your alternator too.

For me my car is a daily driver so I fixed the problem easily.... I drive the car a lot. LOL

 

One of the ways to enjoy a better relationship with a "newer" car is to realize these separate control module really have a deep understanding of whatever sensors and outputs they are in charge of, and their ability to "complain" is a tremendous assistance in any type of diagnostics. Of course, this can only be fully realized when you have some way of properly getting these messages, i.e. a Jaguar-aware code reader. These have come down in price in the recent years and should really be part of the toolbox of anyone servicing these cars themselves at home. Just be sure the device you get is compatible with the earlier cars (my Foxwell device is not, I believe).

In other words, a code proper reader would likely tell you more about what is going on. At the very least, you would have specific codes that you can use to search this forum with, in case this problem has surfaced before.

The other path is to search for the known issues with the older cars: ABS module and its failing circuit boards, ECU rebuild or failed instrument cluster.

Best of luck, keep us posted.

 

That would appear to eliminate the level sensor as the cause of the warning illumination .......

Graham