ABS light comes on after moving forward

[cgramona]

I have a 1996 Taurus LX with 136K with an ABS light problem. When I first start the car the light goes off but as soon as I go a few feet forward it comes on and stays on. Is there any code that can be read to detrmine this problem since it only comes on after the car is rolling? I have only seen my mechanic read the codes when the car is stationary, is it possible for the reader to be used when the car is moving?

Thanks

[crankster139]

I've had the same problem on my '99. The ABS light would come on and off periodically, so I changed the breaks. After that no ABS light or code. It may be a faulty sensor, or just a really worn out one. I don't think scanning the codes while the car is in motion would do anything different.

[irish30]

It could be a wheel speed sensor but I would look more at the ABS ring on the half shafts or axle shafts. Jack up the front of the car so both wheels are off the ground. You will have your parking brake on before jacking up so put the car in nuetral. Carefully and closely look at the silver metal ring that is on the axle shaft. It is between the C.V. boot and the steering spindal or knuckle. Turn the wheel slowly and see if there is any cracks in the ring. Check both wheels for damage or cracks. If there is the ring needs to be replaced. The wheel speed sensor will register a larger gap where the crack is and set the light on.(in a nut shell)

[cgramona]

I did as you said and the rings did not have any cracks. I cleaned them with a toothbrush as they had some mud on them. I also removed the rear wheels and one of the sensores was cacked with mud and I cleaned them as well and inspected for cracks - no cracks. I did cleck the fluid and it was abut 3 ounces low and a litttle brown looking and I topped it off. But after all that the light still comes on a about 10mph.

I did notice tsb CQB 99-16 - Anti-Lock Brake System Lamp Illuminated Has Diagnostic Trouble Codes C1165 and/or C1175. But I don't know how to read these codes. Since the light only comes on after you are moving is it unlikely that this is the code? The fix is to remove blow out any moister in the abs control module conector - which I done 0 but not the full thing of soldering the eylets and filling with some kind of grease.

I think it is a sensor as well any way that I can tell WHICH one it might be or do I need to take it into the shop?

Thanks.

[irish30]

You need to disconnect the speed sensor connector. You wiil need an ohm meter. Measure the resistance between the pins of the brake anti-lock sensor. Not the connector, the sensor terminals. There are two terminals on speed sensor. If the resistance is between 1280 and 1920 ohms then you need to service or replace the wiring. If it is not then you need to replace the sensor. These readings are out of the 1996 shop manual, pinpoint test diagnosis, from Ford.

[cgramona]

Originally Posted by irish30

You need to disconnect the speed sensor connector. You wiil need an ohm meter. Measure the resistance between the pins of the brake anti-lock sensor. Not the connector, the sensor terminals. There are two terminals on speed sensor. If the resistance is between 1280 and 1920 ohms then you need to service or replace the wiring. If it is not then you need to replace the sensor. These readings are out of the 1996 shop manual, pinpoint test diagnosis, from Ford.

I guess this implies that the correct reading for a sensor is between 1280 and 1920 and if the reading is in that range then it must be the wiring UNLESS of course it is another sensor that is the problem. So I think that I would need to test all four sensors to see if any one of them falls outside this range - if one does then it is probably bad - if all are within the range then it must be the wiring or something else. I guess the shop manual assumes you already know which particular sensor is causing the problem perhaps from a code. Does that sound correct?

[irish30]

As long as you are sure that the exciter rings(ABS rings) are good, then yes, you need to check the resistance of the sensors.The codes c1165 and c1175 are rear wheel speed sensor failure codes. The first one c1165 is the Right Rear and the other is the Left Rear.

[Roccer]

I'm also having problems with an ABS light that stays lit. I recently replace a sensor on the tranny when it wouldn't shift from first gear. That corrected that problem. Where is the wheel speed sensor located on a 96 Taurus? Is it the same sensor?
Thank you,
Richard

[shorod]

Originally Posted by cgramona

I have a 1996 Taurus LX with 136K with an ABS light problem. When I first start the car the light goes off but as soon as I go a few feet forward it comes on and stays on. Is there any code that can be read to detrmine this problem since it only comes on after the car is rolling? I have only seen my mechanic read the codes when the car is stationary, is it possible for the reader to be used when the car is moving?

Thanks

You wouldn't happen to be near Cedar Rapids, Iowa, are you? If so, I have an OTC Genisys scan tool with the ABS software and can read the codes as well as monitor the 4 wheel speed sensor circuits real-time while riding in the car. If you can find a shop that has the OTC Genisys or maybe the Snap-On reader with the ABS software, they should be able to do the same.

From your symptoms, I would bet that you have at least one circuit that is not reading accurately, either open or shorted.

I just fixed a friend's Malibu that was doing the same thing. As soon as he started moving forward after backing out of the driveway the ABS light would come on. While monitoring the readings the tool showed that on left hand turns the right front speed reading would drop to zero until the steering straightened out. Of course he always backed out of his driveway the same direction. On that one, the wiring to the sensor was too tight and on left turns would pull the connector enough to make an intermittant connection.

Fixed another Chevy that would set the ABS light the first time of the drive she hit a large bump. On that one, the right front ABS sensor wire was pinched between the lower control arm and spindle. Everytime she hit a bump the wire would open and the sensor would read a wheel speed of zero momentarily. Had to replace a section of wire and properly route it.

-Rod