For some unknown reason the ABS and Parking Break Lights come on every once in a while. Does anyone know why this may be happening? I've checked the sensors on both the Master Cylinder and the Rear End and they don't seem to be loose or broken. If anyone has any helpful insight to this problem, it would be greatly appreciated. Thanks!!

 

Warning Lamp Indicators

The red BRAKE warning light is constantly monitored by the anti-lock electronic control module. If the red light illuminates, the anti-lock electronic control module will disable the RABS II system and turn on the yellow RABS light. For this reason, diagnosing and resolving any base brake concerns illuminating the red BRAKE warning light will, in most cases, resolve a perceived RABS II concern.


Brake Light Self Check

The red BRAKE warning light is used to indicate a low fluid level condition or parking brake applied condition. To check this light, insert the key in the ignition switch (11572) and turn it to the START position. The light should glow in this position. If it fails to glow, go to the «Symptom Chart» .

Allow the key to spring back from the START position to the RUN position. At this time the BRAKE warning light should turn off. If it does not turn off, recheck the parking brake switch to make sure that it is fully disengaged. In the event that the BRAKE warning light remains on, go to the «Symptom Chart» .

 

thanks!! btw, where can i find the "Sympton Chart"

 

In the 1995 Ford F Series Truck Shop Manual.

Symptom Chart -- Rear Brake Anti-Lock Control

There are times when a customer concern will not cause the yellow REAR ABS warning light to illuminate or a code to be stored.

The symptom chart is intended to give the technician a starting point in resolving these types of concerns. The chart also describes conditions that will illuminate the yellow RABS light.

Please note that both the red BRAKE warning light diagnosis procedure and test drive are required prior to performing the tests in this section. Failure to perform these procedures will greatly diminish the effectiveness of this method of diagnosis.

Condition(s):
Red Brake Warning Light Does Not Self-Check
Red Brake Warning Light Stays On When Key Is in RUN Position
Yellow Rear ABS Warning Light Does Not Self-Check
Yellow Rear ABS Warning Light Self-Checks OK, but Light Automatically Begins Flashing
Yellow Rear ABS Warning Light Self-Checks OK, but No Diagnostic Trouble Code When Diagnostics Are Started
Yellow Rear ABS Warning Light Flashes Two Times When Retrieving Diagnostic Trouble Codes (Code 2)
Yellow Rear ABS Warning Light Flashes Three Times When Retrieving Diagnostic Trouble Codes (Code 3)
Yellow Rear ABS Warning Light Flashes Four Times When Retrieving Diagnostic Trouble Codes (Code 4)
Yellow Rear ABS Warning Light Flashes Five Times When Retrieving Diagnostic Trouble Codes (Code 5)
Yellow Rear ABS Warning Light Flashes Six Times When Retrieving Diagnostic Trouble Codes (Code 6)
Yellow Rear ABS Warning Light Flashes Seven Times When Retrieving Diagnostic Trouble Codes (Code 7)
Yellow Rear ABS Warning Light Flashes Eight Times When Retrieving Diagnostic Trouble Codes (Code 8)
Yellow Rear ABS Warning Light Flashes Nine Times When Retrieving Diagnostic Trouble Codes (Code 9)
Yellow Rear ABS Warning Light Flashes 10 Times When Retrieving Diagnostic Trouble Codes (Code 10)
Yellow Rear ABS Warning Light Flashes 11 Times When Retrieving Diagnostic Trouble Codes (Code 11)
Yellow Rear ABS Warning Light Flashes 12 Times When Retrieving Diagnostic Trouble Codes (Code 12)
Yellow Rear ABS Warning Light Flashes 13 Times When Retrieving Diagnostic Trouble Codes (Code 13)
Yellow Rear ABS Warning Light Flashes 16 Times When Retrieving Diagnostic Trouble Codes (Code 16)
Intermittent Problem Suspected
Rear ABS and Speedometer Are Not Functioning Correctly
Unwarranted RABS Activity
One or Both Wheels Lock Up
Hard or Soft Brake Pedal
Lack of Deceleration During Medium/Hard Brake Applications