If the lights are on the cruise control won't turn on. If you turn on the lights while the cruise control is working it immediately shuts off. Any suggestions on where to look? I am thinking wires are shorted somewhere in the harness.

 

Be sure all your rear lights are working properly. Possibly a filament problem in a bulb.

 

What the two systems have in common is the Stop Light Switch.

 

Ditto, might be that brake switch.


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Check that the tail lights are properly grounded.

 

Thank you everyone for your help. I put new bulbs in the. Brake lights and the cruise works perfect!

 

Was it a burned out bulb? If not why wasn't the lamp out bulb on the dash lit then?


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If a filament of the tail light would break and fall against the filament of the brake light, it would power the brake light, and also back feed the circuit to think the brakes are being applied, not allowing the cc to work. I saw this years ago when a vehicle wouldn't go into lock-up because the ECU thought the brake was being applied. When you apply the brake, the transmission would come out of lock-up so the car wouldn't stall.

James

 

Wow, absolutely wild! Once in a million fault? I couldn't even have guessed... Amazing...


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