Having an issue with 1998 Blazer LT 4 door. Courtesy lights will not turn off. Had t pull the fuse to keep battery from draining. Dome light override non-functional. Tested all door switches with volt-ohm meter, all OK. "Gate Ajar" light comes on and off normally when liftgate is opened/closed. Also, radio does not turn off with key as normal. This is driving me nuts. I have replaced/tested the relays associated with this issue, also replaced the control module for lights and courtesy lights. Another issue which could be related is the running lights do not work, its as if the auto switch thinks its dark outside and turns on the headlights so they are constantly on as well. Replaced the light sensor in the right speaker grille, no change. Am I the only one blessed with these problems? Any help is appreciated.

 

Is your door closing all the way? I had problems similar to this when my door pins were worn through and the door wasn't closing properly. After I got the door taken care of the problems stopped. Also, which headlights are coming on? The high or low beam? These cars have daytime running lights so it might be just a normal function for the headlights to be on during the day.

 

Replaced the door pins a year ago due to wear, no courtesy light problem at that point. Removed the switch and forced closed, problem persists. Lights are on low beam, but LEDs (time, mileage, etc) too dim to read in daytime. I thought the running lights were different from the low beams? Also, taillights stay on constantly as well.

 

Yeah, the running lights should be using your high beam, at a lower power level than normal. At least, that's what I've always noticed them to do. You might want to try swapping the headlight/dimmer panel.

 

Swapped headlight/dimmer panel also, no change. Cant think of what else to do. Is the daylight sensor the one in the speaker or the one in the center of the dash vent?