Electrical problems My son owns a 2003 Bonneville and is having intermittment problems with his brake lights staying on all the time. The engine warning light is also coming on/off and the cruise control works/does not work sometimes. Anyone have any suggestions what to check?

First you need to have EBCM - electronic brake control module check for DTC'S - diagnostic trouble code's . If the light is on there is a code stored . I think most part stores can do this and for free . After you find out what code is stored , looking up that code in service repair information for diagnostic trouble shooting chart would be next step . There are a few codes too.
DTC C0035 or C0040
DTC C0045 or C0050
DTC C0110
DTC C0131
DTC C0161
DTC C0186
DTC C0196
DTC C0201
DTC C0240
DTC C0241 or P0856
DTC C0244 or P1689
DTC C0245
DTC C0283
DTC C0287
DTC C0290 or C0292
DTC C0455
DTC C0550
DTC C0558

Find the code do the diagnostic's , fix the problem , wiring issue's , a sensor , bad module ,what ever it is . The light will go out then . Here is a sample of code discription .
• DTC C0035 Left Front Wheel Speed Sensor Circuit
• DTC C0040 Right Front Wheel Speed Sensor Circuit

ABS light on did they check codes ? The light staying on an no codes is usually a insturment cluster problem not the EBCM - electronic brake control module . No relay in side the module , a transistor or diver as they call them . This transistor will supply a ground on a electrical circuit from the brake lamp driver module ,when it does this the brake lamp driver module ground a electrical circuit for the ABS light . If anything is bad causing the ABS light to stay on it would be the brake lamp driver module . Your best bet ,take it to a GM service dept.

bonnevilles run a supercharged engine if the belt connected to the supercharger is worn, missing or severly loose it will cause those sort of problems

Check the parking brake light switch which is located under the center module, remove the cover around the parking brake and you'll find it there.

When you have the service light come on all the time is simply indicates that there are detected error codes by the car computer that requires an attention.

It does not necessarily mean that it is a problem that will make the car not to run but you will need to get a scantoool to enable you determine what the actual issue is.

Please scan the car.

Cheers.

An intermittent electrical problem can be maddening to fix. I have a similar problem in my truck. The connection to the engine fuse in the interior fuse block is loose. If I wiggle the fuse to re-establish contact, the engine will restart.

Next time the engine stalls, notice which of the lights illuminate on the dash. Compare this to which lights illuminate when you first turn the switch on and when engine will start. Applying the brakes probably shifts the loose connection enough to cause the engine to stall.

Usually it Means that you are low on Oil or Coolant.

get the car code read for starters then let me have the code

hi,

had a 97 grand prix and could not get the light out for any period of time, It ended up being the exhaust gas sensor saying incomplete burn due to an intermittent miss, had to change plugs, plug wires and finally injector service but the light stayed out after that, that was a 3.8 V6, hopefully that helps

J