01 SCrew 5.4 Pulled up to stop light, felt like cruise control over rode throttle and went to full throttle. Haven't used cruise in weeks. Brake pedal wouldn't disengage cruise, shifted into neutral, tach Pegged! shifted back into gear and roasted the rear tires with both feet on the brake. Finally shut off ignition. Restarted engine and has acted normally since then. Any ideas?
Thanks, Paxton

 

Check your floor mats to see if it can in any way interfere with the pedal. Check the throttle linkage and cable for any signs of binding. The Cruise control linkage too. The linkage or cable could have bound up and held it there.
Cruise Control not releasing when brakes applied
Possible Source(s):
§ CJB Fuse 15 (5A) and 13 (20A).
§ Circuitry.
§ BPP switch.
§ Deactivator switch.
§ Binding speed control cable.
§ Speed control servo.

Try the following test;

1 Enter Self-Test Diagnostics by depressing the speed control OFF switch while turning the ignition key ON, making sure the engine does not start and is not running. The speed control indicator on the instrument panel will flash once to indicate that speed control module entered the diagnostic mode. FIVE ADDITIONAL FLASHES AT THIS POINT INDICATE A DEFECTIVE SPEED CONTROL SERVO. Release the OFF switch.

2. Press the remaining switches in this sequence: ON, RESUME, COAST and SET/ACCEL.

IF THE "ON" SWITCH IS NOT DEPRESSED WITHIN FIVE SECONDS AFTER ENTERING THE DIAGNOSTICS MODE, THE MODULE TIMES OUT AND THE PROCEDURE MUST BE STARTED OVER.

The speed control indicator lamp will flash as each switch is depressed. Press each switch in the sequence immediately after the indicator light goes out for the previous switch.

3. A lamp flash with the last button (SET/ACCEL) indicates that the STATIC test passed. If the lamp does not flash with the last button and there are no additional flashes of the lamp, the switch is defective.

If the lamp does not flash with the last button, and additional flashes occur, follow the chart below for trouble codes:

— 2 Flashes - BPP defective, circuit is defective, brake applied, CPP switch or jumper (if equipped).

— 3 Flashes - Deactivator switch is open or circuit defective.

4. Immediately after the STATIC test, the speed control servo does a DYNAMIC test by automatically actuating the throttle lever from 8 mm (0.315 in) to 12 mm (0.472 in) of travel from the idle position. During the DYNAMIC throttle pull, observe throttle movement to witness any binding or sticking of the speed control cable and correct connection of speed control cable to throttle lever. Make sure the THROTTLE RETURNS BACK TO IDLE POSITION.

5. Return ignition switch to the OFF position

Regards

Jean MarcChartier

 

JMC,

I just used your procedure detailed to diagnose my cruise control problem. Every thing seems to checkout fine except one thing. In segment 4 of your explaination my truck fails the servo test. There is no cable movement as described yet the servo passes the self diagnosis test you describe.

Would this indicate a bad servo motor? I pulled the servo apart and there is some surface corrosion on the metal parts inside dispite what appears to be a lot of galvanized coatings inside. There is a series of plastic reduction gears that eventually turn the cable actuator. On the cable actuator there is a plastic gear that appears should mesh with a metal gear to engage the cable actuator. Almost like a spline. I turn the gears by hand, everything is smooth and turns freely but that last "splined" gear does not engage with the metal side face of the gear to turn the cable actuator. If I pull the spline together, the cable actuator works fine.

What do you think??

Enigma

 

Enigma,

Is your cruise working properly? If it is leave it as it is. If it isn't please describe the symproms.

JMC

 

JMC,

Passes all tests until #4. Fails DYNAMIC test. Servo does not actuate throttle cable. I actuated the cable by hand and the pull was smooth and consistant. No binding found.

I hear what I believe to be the motor in the servo running when I begin the dynamic test but no cable movement. Very similar sound to a fuel pump when you turn on the key to start the truck.

I a prior post on this thread I spoke about my findings when I partially disassembled the servo.


Also when performing self diagnostic I hear a "knock/thunk" coming from the general area of the servo. Not sure how to interpret that one.

Appreciate you assistance.

Enigma

 

Enigma,

Was there a flash when you pressed the last button during the test? If yes and if the cable is installed properly and there is no dynamic pull then the servo is defective. It is time for a new servo.

JMC

 

My cruise is also not working on my '03. When I run the test it shows all the switches are working, but after pressing the SET/ACCEL button there are 3 flashes. Is the first indicating the switch is working, and the other 2 indicate a bad BPP? Or is it just 3 flashes indicating the deactivator circuit is open? Thanks

 

Is yours affected by the recall? If it is, and you have not had the recall done, do so IMMEDIATELY. It's a fire hazard.