This was originally posted in another area of our board. I am not suggesting that you ignore a recall from ford, but thought I would share a little information. The last I heard, Ford did not have a fix for the problem and only unhooked the cruise control.
There is a self diagnostic check that you can perform for the speed control to see if you have a malfunction. The following instruction "highlights" are taken from my 1998 Mark VIII Ford Workshop Manual. I am posting this to help everyone understand what the "Deactivator Switch" does, and how to run the test. As mentioned, these are highlights, so, if you want to read it all, go to page 310-03-1 of the manual. As always, use this information at your own risk.
There are 5 components for the Vehicle Speed Control. They are:
1 - 9F924 - Deactivator Switch - right front wheel well
2 - 9C888 - Speed Control Actuator Switch - steering wheel
3 - 9E731 - Vehicle Speed Sensor - transmission
4 - 13480 - Brake Pedal Position (BPP) Switch - brake pedal
5 - 9C735 - Speed Control Servo - left front wheel well
This is what the manual says the function of the "defective" part mentioned in this thread - Deactivator Switch does:
The deactivator switch is a normally closed switch. The deactivator switch replaces the speed control dump valve (9C727) as a redundant safety feature in the system.
o Under normal conditions, when the brake pedal is applied, an electrical (brake on/off) signal from the stoplamp circuit to the speed control servo will disengage the system.
o Under increased brake pedal efforts, the deactivator switch will open and remove power to the speed control servo, releasing the throttle from the servo control.
The deactivator switch is located at the front RH frame rail to the rear of the air suspension compressor.
Self-Test Diagnostics
Warning: THIS TEST IS A KEY ON ENGINE OFF (KOEO) TEST ONLY THAT IS CONDUCTED IN PARK ONLY WITH EMERGENCY BRAKE FULLY ENGAGED.
o Enter Self-Test Diagnostics by depressing the speed control OFF switch while turning the ignition key ON, ensuring engine does not start and is not running. The speed control indicator lamp on the instrument panel will flash once to indicate that the speed control module entered the diagnostic mode. Five additional flashes at this point indicate a defective speed control servo. Release the OFF switch.
o NOTE: If the ON switch is not pressed within 5 seconds after entering the diagnostic mode, the module times out and the procedure must be started over.
Press the remaining switches in this sequence: ON, RESUME (RSM), COAST (CST), and SET/ACCEL.
o The speed control indicator lamp will flash as each switch is pressed. Press each switch in the sequence immediately after the light goes out for the previous switch.
When the test is completed, it will tell you the following:
After all five speed control switches have been pressed, the indicator lamp will flash to indicate a Pass or Fail:
- 1 Flash - (with dynamic throttle pull).
- 2 Flashes - BPP switch defective, circuit defective, or brake pedal applied.
- 3 Flashes - Deactivator switch is open or circuit defective.
- 4 Flashes - Vehicle speed signal is out of range or not connected.
o Immediately after the passed STATIC test, the speed control module then performs a DYNAMIC test automatically by actuating the throttle lever from 1mm to 10mm of travel from the idle position. During the DYNAMIC throttle pull, observe the throttle movement to witness any binding or sticking of the actuator cable, proper connection of the actuator cable to the throttle lever, and ensure the THROTTLE RETURNS BACK TO IDLE POSITION.
o Return ignition switch to the OFF position and proceed to the following Symptom Chart, if necessary.
If quizzes are quizzical, what are tests?
There is a self diagnostic check that you can perform for the speed control to see if you have a malfunction. The following instruction "highlights" are taken from my 1998 Mark VIII Ford Workshop Manual. I am posting this to help everyone understand what the "Deactivator Switch" does, and how to run the test. As mentioned, these are highlights, so, if you want to read it all, go to page 310-03-1 of the manual. As always, use this information at your own risk.
There are 5 components for the Vehicle Speed Control. They are:
1 - 9F924 - Deactivator Switch - right front wheel well
2 - 9C888 - Speed Control Actuator Switch - steering wheel
3 - 9E731 - Vehicle Speed Sensor - transmission
4 - 13480 - Brake Pedal Position (BPP) Switch - brake pedal
5 - 9C735 - Speed Control Servo - left front wheel well
This is what the manual says the function of the "defective" part mentioned in this thread - Deactivator Switch does:
The deactivator switch is a normally closed switch. The deactivator switch replaces the speed control dump valve (9C727) as a redundant safety feature in the system.
o Under normal conditions, when the brake pedal is applied, an electrical (brake on/off) signal from the stoplamp circuit to the speed control servo will disengage the system.
o Under increased brake pedal efforts, the deactivator switch will open and remove power to the speed control servo, releasing the throttle from the servo control.
The deactivator switch is located at the front RH frame rail to the rear of the air suspension compressor.
Self-Test Diagnostics
Warning: THIS TEST IS A KEY ON ENGINE OFF (KOEO) TEST ONLY THAT IS CONDUCTED IN PARK ONLY WITH EMERGENCY BRAKE FULLY ENGAGED.
o Enter Self-Test Diagnostics by depressing the speed control OFF switch while turning the ignition key ON, ensuring engine does not start and is not running. The speed control indicator lamp on the instrument panel will flash once to indicate that the speed control module entered the diagnostic mode. Five additional flashes at this point indicate a defective speed control servo. Release the OFF switch.
o NOTE: If the ON switch is not pressed within 5 seconds after entering the diagnostic mode, the module times out and the procedure must be started over.
Press the remaining switches in this sequence: ON, RESUME (RSM), COAST (CST), and SET/ACCEL.
o The speed control indicator lamp will flash as each switch is pressed. Press each switch in the sequence immediately after the light goes out for the previous switch.
When the test is completed, it will tell you the following:
After all five speed control switches have been pressed, the indicator lamp will flash to indicate a Pass or Fail:
- 1 Flash - (with dynamic throttle pull).
- 2 Flashes - BPP switch defective, circuit defective, or brake pedal applied.
- 3 Flashes - Deactivator switch is open or circuit defective.
- 4 Flashes - Vehicle speed signal is out of range or not connected.
o Immediately after the passed STATIC test, the speed control module then performs a DYNAMIC test automatically by actuating the throttle lever from 1mm to 10mm of travel from the idle position. During the DYNAMIC throttle pull, observe the throttle movement to witness any binding or sticking of the actuator cable, proper connection of the actuator cable to the throttle lever, and ensure the THROTTLE RETURNS BACK TO IDLE POSITION.
o Return ignition switch to the OFF position and proceed to the following Symptom Chart, if necessary.
If quizzes are quizzical, what are tests?