when the truck is in cruise control (around 55) and i have to slow down, i hit the "coast"button to slow down a few mph's.. except now, when i hit the "coast" button, the entire cruise control shuts off and when i try to put the truck back into cruise control, nothing happens.... then, when i try to engage cruise again, after about 3 minutes, it works fine. everything even "coast' then, the cycle starts again!
what do you guy's think the problem is?

 

This came in handy for me, maybe it'll be useful to you too.

Self-Test Diagnostics

WARNING:
This test is a key on engine off (KOEO) test that is only conducted in park with emergency brake fully engaged.

l 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 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.

l Note:
If the ON switch is not pressed within five seconds after entering diagnostic mode, the module times out and the procedure must be started over.

Press the remaining switches in this sequence: ON, RSM (resume), CST (coast) and SET/ACCEL.

l 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.

l Note:
There will be a slight delay when the last button is pressed and the lamp flashes.

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 the additional flashes occur, follow the list below for trouble codes:

— 2 flashes: Brake pedal position (BPP) switch is defective, circuit is defective, or brake pedal is applied; clutch pedal position (CPP) switch is defective, circuit is defective, or clutch pedal is applied.

— 3 flashes: Brake deactivation switch is open or circuit is defective.

— 4 flashes: Vehicle speed signal is out of range or circuit is defective.

l Immediately after the static test has passed, the speed control servo will carry out a dynamic test automatically by actuating the throttle lever from 1 to 10 mm (.04 to.39 inches) 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, verify the correct connection of the speed control cable to the throttle lever, and make sure the throttle returns back to the idle position. If incorrect connection and/or binding or sticking of the speed control is observed, go to the Symptom Chart.

l Return the ignition switch to the OFF position and proceed to the Symptom Chart.


Symptom Chart

Note:
Self-test diagnostics must be carried out before proceeding to the Symptom Chart.


Condition(s):

o The speed control is inoperative — no flash codes

o The set speed fluctuates

o The speed control does not disengage when the brakes are applied

o The speed control does not disengage when the clutch is applied

o The speed control switch is inoperative

o Flash with last switch pressed and dynamic pull occurs at the throttle

o Flash with last switch pressed, but no dynamic pull occurs at the throttle and the speed is control inoperative

o Flash with last switch pressed, dynamic pull occurs at the throttle and the speed is control inoperative

o Flash Code 2 — brake pedal position switch circuit failure

o Flash Code 3 — deactivator switch circuit failure

o Flash Code 4 — speed signal circuit failure

o Flash Code 5

o The speed control indicator lamp is always on

o The speed control indicator is inoperative

 

Thank you so much for that diagnostic guide. I used this just now as I've been having a recent problem with my 2008 Ranger speed control.

Specifically, it turns on fine, and locks in the chosen speed. However, after a few minutes (as few as 5, as many as 15) the speed control simply "drops out". That is, the dash indicator is still on, but all speed control ceases. Pushing resume, accel or decel does nothing. If I turn it off and then on, it catches 2/3 of the time, but doesn't hold speed for long.

SO - I found this page and today tried the diagnostic test. Took a few tries to get the timing correct on the button pushes. It seems as if the first several tries of the test would not go past the resume button push. Powered up OK, pressed "on" (OK - light), pressed "Resume" ... nothing. This happened several times, then two time in a row I was able to complete the test (all buttons OK, dynamic test OK - no error light blinks at all).

This ranger (2008, FX4) has the speed control as buttons on the left and right spokes of the steering wheel.

I'm thinking from the way the test(s) ran, that perhaps the right button set (resume/accel and coast) or a least the resume/accel button is going bad.

Would a flakey resume/accel button cause the speed control to cut out when operating? I also checked the OBDII port and there are no error codes for the truck.

Thanks.

 

I had a similar cruise control problem, which is now (yesterday) fixed. It was the servo that went bad.

I had exhausted every other possibility, but new servos are $380 on Ebay and $450+ from dealers. Phoning around at wrecking yards, I found one out of the same year and model Ranger for $65. Picked it up and installed it in the parking lot as they are VERY easy to swap out. New (well, used) one worked perfectly.

I took apart the broken one. They are a very simple device - there is a fairly complex circuit board behind protective gell on the side, a servo motor with 4 connections and a magnetic clutch with two connections. My guess is it's either the circuit board or the magnetic clutch OR the plastic gears meshed by the magnetic clutch that failed.

What really annoys me about this whole process is that this servo is obviously (to me) something that could very easily be bench tested to see if it's A-OK or not. A simple plug harness (or even bare connections) could be applied and you'd quickly know if the board, servo, clutch or gears were bad (or it was all good). But in all my months of internet searching and dealer calling, there is nothing. The Haynes books are worse than useless regarding speed controllers, and the dealer always just said "bring the truck in". At $450+ for the new servo, that's not going to happen.

So - anyone out there - have you heard of a bench test setup for speed control servos like this?

 

It’s hard for me to understand what you’re saying with a different flashes. I hold off. Then I press each of the buttons you say in the sequence you say, the light flashes after each button press. Than no more flashes?