I started my Blazer last night and discovered the instrument cluster lights, tail lights and 4wd did not work. Fuses are good. Has anyone experienced this? How did you resolve it? TIA.

 

In what way did 4wd fail. No lights, flashing lights and no transfer case activity, transfer case activity and improper engagement?

are you sure that all three items failed simultaneously?


George

 

The 4wd and instrument lights failed simultaneously, I'm assuming the tail lights did as well. Absolutely nothing on the 4wd, no lights on switches, no relay clicking, nothing.

 

Check the following fuses:

pk pls fuse 3, ipfb
4wd fuse 19, ipfb
gauges fuse 4, ipfb
turn b/u fuse 26, ipfb


George

 

Yep, I have checked all fuses, twice. Also the 2 relays in the fuse box. I was hoping there was a common junction, ground, troublesome connector that I was unaware of.

Another question though, what are the 3 relays in the glove box for?

 

Your headlight switch/interior light switch has failed. Happened to me also, no lights, replaced switch with a good one from the junkyard and all lights work.

 

The grounds are common to most of the functions in the front half of the truck and the tail lights are on separate grounds.

Check for voltage into the illum fuse 23 which comes from the dimmer in the dash. If no voltage then the dimmer has failed.

Since you have checked all the fuses, go to the tail lights and find out if you have lost power or ground to the lamps.

George

 

Or you can just go for the switch since that is a high likelihood. I like to verify first so I don’t waste my time and money but some prefer to replace the most likely part straight away. Dealers choice.

If 4wd also does not engage that may be a separate issue

George