Hi David

When you turn on the ignition, all the dash lights will come on but some of them are only for a moment

But the one you are referring to, is the Headlight/Side Light/ (Test Light)

This comes on when you first turn on, either the Headlights or Side Lights and providing they are working this (Test Light) which is on a Timer will go out after about 30 Seconds

Its kind of very useful, as it lets you know you've Switched them on, as that multi function light switch is enough to make your head spin on occasions

 

Okay here is my latest issue. I did a complete brake job, and suctioned out most of the old brake fluid from the reservoir.
My ABS and Brake light come on when ignition first switch and started. This is Normal.
Then after the ECU runs its tests, they go out as they are suppose to. But then after driving a few hundred yards, the ABS light comes back on.
At first it was a dim glow, as if it was pressure sensitive (versus just on or off). So, I bled the brakes again per the Service manual procedure.
(I have Not bled the accumulator or Master cyl however)
The accumulator is charging the system with pressure.
The light now comes back on but it is much brighter now? (Still goes out after start up as Normal, but comes back.)
The brakes feel great and are linear progressive...the harder you push the pedal, the more force exerted.
Could it be a sensor needing cleaning?
(This is always an issue with XK8/Rs. But the real fix was soldering the ground connection in the ABS module itself...if any of you visit the XK8 forum you'll know what I mean.)

 

There is only one way to do this, and believe me I've been there. Start at #1 and test until you find the fault, and you will find it.

 

Hi Steve

When the Car is first Started some people make the mistake (if you could call it that) of driving off, as soon as the Brake and ABS Light go out

Which sometimes results in the ABS light momentarily coming back on

Because even after those lights go out, the System isn't Fully Pressurized and if you listen carefully, even after those lights go out you should be able to hear the Brake Pump is still running

As it usually takes around 49 Seconds to achieve Full Pressure in the Braking System

So next time that you Start the Car listen for the Brake Pump to Cut out, after the lights have gone out before moving off and then you should notice a difference where the ABS Light, should go out and stay out without blinking on

 

Erm, you can drive off with the ABS light on. It will go out BUT the ABS finishes its selfcheck when you pass a certain speed. You should hear a very faint noise every new start passing a certain speed. This is when the sensors are checked.

So, if the light stays off when stationary (start up) but turns on after rolling, then there is an ABS sensor fault. It is just that easy.

 

Time-Pilot...thanks for the link I will run the procedure.

Daim...that's what my system is doing. Light goes out after start up and self diagnostics are run. But then when I "move" or start rolling it comes back on.
Thus I guess it's a sensor?

 

Yep. Most commonly just dirt. Remove the wheels, clean the pick up wheel as well as the sensor and then try again. The sensors don't always go bad.

 

Hi Fla Steve

Re: Your ABS Light problem, something else it could be

First of all if you have drained the Reservoir on the Master Cylinder Actuator, then it is essential to Bleed the Low Pressure Side of the System before you Bleed the Brakes

But if the Reservoir didn't run dry then maybe you won't need to, although I always do it just in case and just as a matter of Course

Also when you refill the Reservoir and you've taken the Top off, have a look down the hole and if you look very closely you will see a dividing baffle plate, which is offset to one side so much that this is easy to miss

So when you refill the Reservoir make sure that you pour Brake Fluid both sides of that easy to miss Divider, as you never know that could be your problem

If you also need to Bleed the Low Pressure side of the System, as I think you might probably will

This is how I did it on my Car 'Cherry Blossom' on Page: 19 of my 'Cherry Blossom' restoration thread and here is a link to that Page: Bleeding the Low Pressure Side of The Master Cylinder Actuator on my 1990 XJS V12

 

Have you tested that the ABS works?
Quiet piece of road, build up some speed and stamp on the brake pedal and see if it steers.
If the wheels lock up then it isn't working.
Don't do it the way I did by arriving unexpectedly in the middle of a herd of deer.