odd cruise control problem

[vroomzoomboom]

2 weeks ago, going down the highway, i went to use the cruise control. i found it was going on, but not after having to press the set accl a few times. last weekend, once again, going down the highway, i went to use it, but this time it wouldnt come on at all.
i tried doing a self test to see what the problem was. after holding the off button, then turning the truck on, the light would flash for the on button, then res, but nothing for the set, or coast. i have a few spare buttons around, so i tried them, and same thing. even went as far as swapping the harness the goes to the buttons to the clock spring (nothing worked). anyone have any ideas?
this is on a 98 sport

 

[1998Exp]

2 weeks ago, going down the highway, i went to use the cruise control. i found it was going on, but not after having to press the set accl a few times. last weekend, once again, going down the highway, i went to use it, but this time it wouldnt come on at all.
i tried doing a self test to see what the problem was. after holding the off button, then turning the truck on, the light would flash for the on button, then res, but nothing for the set, or coast. i have a few spare buttons around, so i tried them, and same thing. even went as far as swapping the harness the goes to the buttons to the clock spring (nothing worked). anyone have any ideas?
this is on a 98 sport

For what it's worth, the self-test of the cc in my '98 Limited never worked, and both times it failed the culprit was the servo itself. Despite the plethora of part numbers, they are all the same, except for the mounting bracket - which you can transfer. If you buy one, make sure it's returnable, because there are plenty of defective ones out there, as the sellers have no way of testing them.

 

[fast_dave]

@vroomzoomboom

Since the Cruise Control was working before, check the free-play on the CC Cable that goes to the throttle body.

There is a clip that allows you to adjust out the free play as the cable stretches.

Over 16 years I had to do this two or three times when my CC wasn't smoothly & seamlessly engaging.

As years go by, if the cable is left unadjusted, eventually so much cable stretch will develop that the arc of the
CC Motor (by the passenger firewall) can't take up all the slack, and you will "lose" your cruise control.

Look at the cable on top that has the clip on it - note the number of "steps" on the plastic adjustment point.

Those adjustment points take up the slack that develops in the cable over 20 + years.

BEFORE ADJUSTING, if memory serves me correctly, you should be able to pull on the "protective but movable BROWN PLASTIC sheath"
(2nd Picture) on the CC Cable to see how much free play has developed before the arm on the throttle body engages.

Hope I'm making myself clear - you've been here long enough (2007) to stand back and take a look at the
whole CC Cable arrangement and figure out what I am saying

Hope that help brother and report back

 

[vroomzoomboom]

For what it's worth, the self-test of the cc in my '98 Limited never worked, and both times it failed the culprit was the servo itself. Despite the plethora of part numbers, they are all the same, except for the mounting bracket - which you can transfer. If you buy one, make sure it's returnable, because there are plenty of defective ones out there, as the sellers have no way of testing them.

@vroomzoomboom

Since the Cruise Control was working before, check the free-play on the CC Cable that goes to the throttle body.

There is a clip that allows you to adjust out the free play as the cable stretches.

Over 16 years I had to do this two or three times when my CC wasn't smoothly & seamlessly engaging.

As years go by, if the cable is left unadjusted, eventually so much cable stretch will develop that the arc of the
CC Motor (by the passenger firewall) can't take up all the slack, and you will "lose" your cruise control.

Look at the cable on top that has the clip on it - note the number of "steps" on the plastic adjustment point.

Those adjustment points take up the slack that develops in the cable over 20 + years.

BEFORE ADJUSTING, if memory serves me correctly, you should be able to pull on the "protective but movable BROWN PLASTIC sheath"
(2nd Picture) on the CC Cable to see how much free play has developed before the arm on the throttle body engages.

Hope I'm making myself clear - you've been here long enough (2007) to stand back and take a look at the
whole CC Cable arrangement and figure out what I am saying

Hope that help brother and report back

View attachment 422412

View attachment 422413

well, thanks for your ideas guys, but you want to know something?

i screwed up! i did the sequence wrong! i did off, on, res SET COAST not off, on, res, coast set! i figured that out this morning. however, once i did it correctly, the cruise light flashed 2 times. either a boo or bpp switch. lucky for me that i have a parts truck or 3 stashed at work that i pulled both switches off tonight. when i got home, i unplugged the switch on the master cylinder and jumped a wire to it. no more code and heard the servo do its thing. put the new used switch in, no more codes.
sorry for being a bone head, but thanks for your help and ideas.