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Discussion Starter #1
Hello All,

Anyone out there have a problem with the cuise control on the STS? I think this may only apply to the 98+ years with the separate cruise paddle low on the right hand side of the column. I can't get the cuise to engage. The "cruise" light comes on when the car starts up and then goes out like normal, but I can't get the cruse to work. I checked the fuse under the hood and it was good. The only thing left I'm thinking is the cruise paddle switch itself. Any ideas? I recently purchased the vehicle, so maybe there's just something I'm not doing right. I don't know.

Thanks.
 

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'98 STS (RIP @ 206,xxx miles)
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Is the button on the end of the stalk pushed IN??

Jim
 

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And you are lifting the stalk toward the steering wheel to engage? And vehicle speed is between 25 MPH and 110 MPH?

Next suspect is one of the two switches on the brake pedal (and I can't remember which one it is). Pull the trim panel under the steering column and you will see the switch bracket. Make sure there not too much clearance (1/8", I THINK) between the switches and the brake pedal. Be sure to measure at the barrel, and not the plunger.

The switches rotate about 45 degrees to remove/replace and they will ratchet in when you install them. No tools required, other than a 1/8" stack of leaf type feeler guage; 0.125".

I set mine to 0.080" cause I like my brake lights ON as soon as I touch the pedal.

Good luck.
 

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Discussion Starter #5
JimD said:
And you are lifting the stalk toward the steering wheel to engage? And vehicle speed is between 25 MPH and 110 MPH?

Next suspect is one of the two switches on the brake pedal (and I can't remember which one it is). Pull the trim panel under the steering column and you will see the switch bracket. Make sure there not too much clearance (1/8", I THINK) between the switches and the brake pedal. Be sure to measure at the barrel, and not the plunger.

The switches rotate about 45 degrees to remove/replace and they will ratchet in when you install them. No tools required, other than a 1/8" stack of leaf type feeler guage; 0.125".

I set mine to 0.080" cause I like my brake lights ON as soon as I touch the pedal.

QUOTE]

Jim,

Wouldn't too little clearance cause the cruise not to engage because the computer would think the brake is being depressed? How is too big of a gap affecting the engagement? Does it need to sense the pedal position before it will kick on?

Thanks for your input on this. I really appreciate it!
 

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The switches are sensing if the the brake pedal is NOT in the "relaxed" position. Brake pedal action affects several systems and one of them is the cruise control; another is the stop (brake) lights and another is the transmission torque converter lock-up mechanism and another is transmission shift interlock (apply brakes to shift out of Park). The logic is in the vehicle PCM.

With no pressure on the brake pedal, some circuits are closed and others are open. Moving the brake pedal some minimal amount activates the switches and opens some circuits and closes others to accomplish the desired switching.

If your switches are not adjusted correctly (as in too large a gap), the circuits COULD sense the brake pedal is depressed when in fact the brake pedal is not being touched. Since braking action and cruise action are probably contradictory, the brakes win and the cruise is inhibited.

According to my Service Manual for 1998 Seville, the the barrel to pedal arm clearance is 1/16"; not 1/8" as I wrote earlier. And the upper switch is the one that affects cruise operation. Sorry for the bad information.

Hope some of this is helpful.

Jim
 
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