98" Cruise Control Issues

[kealvarez]

I am having cruise control problems. The cruise on my 98' PA sometimes turns itself off a second after I turn it on. Other times it works normal, and I have not been able to link the issue to anything else. The only recent addition to the vehicle was a used factory (E-Bay) Buick AM/FM/Cass/CD player that replaced my AM/FM/Cass (no CD).
Any help would be greatly appreciated!

[tman]

The problems arent related. This occured on my cousin's regal GS. find your cruise control unit on the firewall. there is a throttle cable for the cruise control going towards the engine. disconnect theis from the unit. there is a cloth piece, yellow in color. This is where my cousin's regal went wrong. I think only the CC throttle cable needs to be replaced, the unit, i believe is fine.

[kealvarez]

I checked out the yellow cloth strap, but it looks to be in excellent condition. Any other suggestions?

[GSteven]

I have a 94 PA ultra. I can set the cruise, the light comes on and it will 'almost' hold sometmes. This means that it will hold the correct speed if I am on a slight downhill stretch or drafting on the flat, but when I hit an incline I lose speed.

Does this sound like the same issue you have? Did you ever find any answers?

thnks
Steve

[GSteven]

I'm preparing to go on an extended trip at the end of this month. It sure would be good to have cruise. Anybody have any ideas on what this issue could be?
tia
Steve

[kealvarez]

I've had this problem for 2+ years now. Has anyone discovered a solution.
The problem:
The cruise control works inconsistently. It turns on and holds the correct speed, but at no reproducible time it turns itself off (light goes off and it begins to lose speed). I can turn it back on and it will hold for a length of time until it shuts itself off again. I have not linked it to anything (other electrical equipment operating, speed, weather, road roughness, etc.). Some days it holds for 30minutes at 75mph, others it only holds for a few seconds.
Thank you for any insight!

[TopherS]

Luckily, I haven't experienced this problem, but perhaps this may help in narrowing down the issue...

After the cruise turns itself off, can you "resume" back to the preset speed...or...do you have to completely reset the speed you want?

The reason I ask is that if you can use the resume feature, it would be acting the same as if you had pushed the brake pedal, which turns off the cruise (safety feature), but allows you to resume the same setting. If this is the case, perhaps you have a malfunction in the brake light switch...maybe the cruise control components are receiving a signal from the brake light switch, thinking that you are braking and it turns off the cruise, even though you haven't touched the brake pedal.

If it completely cancels the cruise, then perhaps the switch is faulty, turning itself off, even though you haven't moved it to cancel the speed setting...or the main component is malfunctioning. Sounds like an electrical issue, rather than mechanical.

Hope this helps.

[kealvarez]

Yes, I can resume to the same curise speed.
You may be on to something with the brake pedal switch.
I looked at the brake pedal and there are 2 white plastic blocks with spring loaded buttons that extend when the pedal is depressed. Am I correct to assume one is for the brake lights and one is for the curise? Are these adjustable (maybe I can adjust before replacing?)?
Thank you

[TopherS]

To be honest, I don't know whether one of the contacts is for the brake lights and one is for the cruise. I also don't know if it's adjustable. I wish I could say for sure one way or the other. Perhaps others on the board know. Personally, I would get the hunch that if there is a malfunction in the switch, it probably would not go away by adjusting the contacts. You could also accidentally change the point at which your brake lamps would go on when applying the brakes, putting you and yours at risk of being rear-ended. I would suggest a new switch. It's been a long time since I have replaced a brake light switch, but I don't remember them being all that expensive. But then again, these cars are so electronically complex, that they can charge a king's ransom for the simplest of parts and many of us wouldn't be the wiser. My is to check into a replacement switch and that way (hopefully), the cruise should be functioning properly.

It might also be worth while to speak to a Buick (or even another GM division) dealer service manager and ask if he/she has ever seen this type of problem and if replacing the switch will likely cure it. There's numerous dealers in my area and one service manager won't even venture a guess, he just says "bring it in and we'll see" (and we'll charge $90/hr, too), but at another dealer, the service manager is very helpful and is willing to offer up his experience and will say "yes, I've seen that and replacing this part will probably work" or he will say "no, you're just wasting time/money...most likely, you are looking at (such and such) problem". You might save a lot of time/energy/money by asking around. The worst they can do is offer to strip you of $90/hr .

Good luck, and keep us posted...sounds like others may share a similar problem.

[imidazol97]

Originally Posted by TopherS

Luckily, I haven't experienced this problem, but perhaps this may help in narrowing down the issue...
Hope this helps.

On my 93 there were two electrical circuits through the brake pedal that were required for the cruise control to operate. The switch on one was either out of adjustment or didn't make contact except for occasionally. The dealer replaced the cruise mechanical box and the problem still wasn't fixed. They found there were two circuits through the switches on the brake pedal and t hen the problem was fixed. The refunded my cost for the box and put it back in to stock.

I'll check my 98 book when I get time as to the circuits for cruise through the brake pedal. Does it always reconnect with just the resume button and does it release with a bounce or bump in the road?