DRL not working
#2
Senior Member
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DRL daytime running lights? the dash should have a little sensor popping out of it somewhere in near the windshield or sometimes its in the rear view mirror. did u checked it?
#3
Senior Member
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True Car Nut
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The DRL system will make your headlamps come on at a reduced brightness when:
- the ignition is on,
- the headlamp switch is off,
- the parking brake is released and
- it is bright enough outside and the automatic headlamps are off.
When the DRL are on, only your headlamps will be on. The taillamps, sidemarker and other lamps won’t be on. Your instrument panel won’t be lit up either. When it begins to get dark, your DRL will turn off. Your headlamps will come on automatically. When it begins to get bright, the regular lamps will go off, and your headlamps will change to the reduced brightness of DRL. To idle your vehicle with the DRL off, set the parking brake. The DRL will stay off until you release the parking brake.
- Check to see all the conditions for turning on the DRL'* are met (ignition on, headlamp switch off, park brake released, bright outside, and automatic headlights are off.
- Check the outside of the vehicle to see if the headlights are lit (when all the above conditions are met). Need to know if the DRL system is malfunctioning or it is just the DRL indicator light burnt out.
If none of the above leads to a solution, let us know and we will think about next steps.
#7
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Found the part that was bad. It is under the dash and looks like a big heat sink. Not sure what its call or the part# if someone can help. I am attaching a photo. If you bang it it works, chacked the conections and all is ok so am guessing it is going bad.
#8
Senior Member
True Car Nut
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is there one orange and one yellow wire on it? on the diagram there is a module but it has 8 inputs. there is a diode just called diode 203 though that would only have two pins
#10
Senior Member
True Car Nut
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see if there is a gm part # on it and google it. the diagram shows a diode but its in the high current side so i can only imagine its a resistor to knock down the light output when the drls are on because diodes dont need big heat sinks like that. but the diagram doesnt show any resistor