2003 Chevy Impala Dash Lights Stopped Working


#1

I have a 2003 Chevy Impala LS with 120,000 miles, equipped with sentinel lighting. Recently, the instrument cluster lights along with the lighted controls on the door panels and steering wheel stopped working leaving me unable to see the speedometer while driving at night. All controls seem work properly. I did some internet research and it appears there are several causes and/or fixes out there. I would like to have one or two more probable approaches than just throw money and time at a trial and error approach. Does anyone have any experience with this that they could provide some “most likely” solutions?? I greatly appreciate the help!


#2

Sorry, I forgot to mention that I checked the two fuse panels and all seem to be okay.


#3

The sentinel is just a sensor that reacts to outside light to control exterior lighting. It could also control interior lighting so that sensor needs to be checked. Does your Impala have a rheostat that controls the brightness of the lights? Most of these rheostats can be turned completely off. I know that’s the case with my truck and my wife’s Blazer. Check and see if that control is working properly.


#4

The Body Control Module controls all the interior lighting.

If it is the BCM, the new BCM will need to be programed with a scanner so it will communicate with the PCM.

Tester


#5

More than likely it’s a bad headlight switch.


#6

Thanks for the data @knfenimore. It could be the light switch causing the trouble. As the drawing shows, the switch inside the BCM makes a ground connection to turn on the PARK LP RELAY.

You should have at least a test light probe to check for power. Fuses can be good but if power isn’t getting to them you still have nothing. You need to find where power is being interrupted. The relay contacts could be bad. Power input to relay could be missing also. The test light will show what is happening at the various test points. With the light switch turned ON check for power on the fuse after the relay. If you don’t have power there then turn the light switch to OFF and check for power on the white wire going to pin F1 that ties to the relay coil. If the light turns on slightly then you have power getting to the relay. Now turn the light switch ON, if the switch to ground is good the test light should turn OFF. If it doesn’t then the switching inside the BCM is bad or there is a fault in the wiring to it. You could force a ground on pin F1 if that is the case to prove the light circuit function. If you have no light with the switch turned OFF then power to the relay needs to be checked. It most likely comes from a fuse under the hood. If the test light goes out when the light switch is turned on then suspect a bad relay. If all of those things check out ok then check for power on the STR COL fuse after the dimmer switch. If no power is getting that fuse then the dimmer control or the wiring too it has a problem.


#7

I suppose that letting a computer have complete control over the lights in your vehicle is supposedly a step forward in progress. I think it’s a few steps back…in my opinion.


#8

In some cars I have owned, the brake lights and the instrument panel lights are on the same circuit. As a safety measure, check to be sure your brake lights work. If they are out as well, check for a problem on this circuit.
I lost all instrument panel lights on a 1990 Ford Aerostar. It turned out to be the rheostat that controls the brightness of these lights had burned out.


#9

Triedaq: The brake lights are working fine as are all the other lights and controls.

missileman: The dimmer control on the light switch does not work. It does not change the intensity of the lights. I think this is what you were asking.

Thanks everyone for your input. I guess the easiest thing to try would be the new headlight switch.


#10

You can certainly guess at what is causing the trouble and you might get lucky and solve the trouble on the first try. If you do the testing I mentioned earlier it will lead you to the fault.