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Let's Revisit My Cruise Control Problem-Please

927 Views 11 Replies 3 Participants Last post by  StuJac
Ok-back for more advice on the cruise control problem with my 98 Deville. It works, on average, 90% of the time. When the car is warm/hot, it sometimes won't come on until I slam on the brakes. Occasionally, while driving, it'll disengage and won't re-engage until I slam the brakes. I'm convinced it's the brake switch and I want to replace this myself.

1. Need help from a tech who can tell me if putting in a new brake switch can be done by myself, with very limited tools/patience.
2. Anyone know who much they cost? (brake switch)
3. Anyone think it could be anything other than the brake switch? Or possibley, something in addition to the brake switch.

Much, much thanks in advance.
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Changing the switch should not be hard. It is located at the top of the brake pedal arm. There should be two switches up there. One is for brake lights, one for cruise disengage and the TCC disengage is also controlled by one of them, though I for get which.

The one thing that makes me wonder about you theory, is the fact that you have to "slam" on the brakes. The switch will not know that. It simply opens the circuit whether you slam the brakes or lightly touch them. Perhaps it is simply out of adjustment.
Thanks Ranger. I'll need to know which of the switches operates the cruise disengage and also, how it "adjusts". Thanks for your input. I had a huge trip this morning. Went to pick up the daughter from college in Manhattan, deliver her to JFK Airport and get back to work in PA. Cruise was almost perfect all the way up (95 miles) but fought me all the way back. It is true that sometimes it seems that it'll only reset when the brakes are hit hard, versus just tapping them.

What do you think they get for that switch? About a grand? :bigroll:
OK, I stand corrected. Per the '03 FSM there is only one switch (Brake lamp, TCC/Cruise disengage), and it is self adjusting. I was thinking of the old ones. If your brake lights are working, the switch is OK. To remove it (if necessary) just twist counter clockwise and pull it out. Have someone watch the brake lights while you gently press on the pedal and see if you can get them to not illuminate.
That makes the issue of being able to reactivate the cruise by hitting the brakes much stranger. The brake lights work, btw. Now what?
Not sure. Maybe just an intermittent connection somewhere. I'd pull, inspect and clean if necessary all the cruise connections. If that does not help, then it's time for a FSM, unless someone else has any ideas.
So, now I've discovered how to get the cruise to operate properly every time. I was on my back from AC (a $140 loss at the Tropicana poker room :rant2: :rant2:). When it disengages, or won't come on initially, I can put my foot behind the brake pedal and push upwards ever so slightly and, works!! Guess that's evidence of a bad adjustment on the brake pedal or the disengage switch. But, I was able to get it back on each and every time I used this new method. :)
Yup, just adjust that switch and you are back in business.
Any hints on that, Ranger? Does it adjust up or back, left or right, front to back? What tool? A screwdriver? Will I see it immediately?

Thanks much,

I don't know about your car specifically, but every one I've dealt with on other cars has a threaded shaft and a nut or collar that locks it into place. You may have to remove the under-dash panel (or not) but just follow the brake pedal up and you should find it. Should take either an open end or pliers to adjust if I'm right about the mounting method.
Follow Chubby's advise. My '03 manual says it is not adjustable. Not sure about the '98. You'll just have to look and see. Once you see it, it will become apparent how to adjust it if it is adjustable.
Thanks again guys. I took a look and there's a shroud covering everything above the brake pedal. I think I'll just try my stop-gap method rather than try to figure out how to get the shroud off.
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