light issues affecting guages

[warrpath4x4]

I have a 88 K5 that when i turn the headlights on (running lights or headlights) my fuel guage drops to empty and my temp guage tops out. Turn the lights off and they go back to normal. When i turn my turn signals on all the guages bounce (minus speedo).

I know alot of light issues can be fixed with a new light switch or if it has a floor dimmer, the dimmer on this is in the column, and i plan on getting a new headlight switch on payday (even if it doesnt need changed its a cheap part to replace)

Any suggestions on what it could be?

 

[jeff in co]

I just did a conversion from cable speedo to the electric speedo but down in the thread, you should see some pics of my instrument cluster plug and the colors for each wire. I would assume your 88' would be identical to the 89' so it may be worth looking at. You could at least double check your plug to be similar (but I guess I can't imagine why they would be different). It's just strange that your fuel gauge, blinkers and headlight switch is all tied together.

Other than that, it may be your blinker switch and some of the wiring down in your column. Sounds like some of that is pretty messed up somehow.

http://coloradok5.com/forums/showthread.php?t=296187

 

[warrpath4x4]

ya electrical is not my favorite, i worked on a hummer that had a wiring gremlin that would change everytime, one time you hit the right turn signal and the back up lights would go solid, next time you hit the right turn signal the left headlight would blink. we fought that for 4 days before finding a loose wire inside the headlight housing.

i did a custom dash in my old truck with round face guages, id like to do another one for the blazer but my tools are about 700 miles away

 

[imiceman44]

I have a 88 K5 that when i turn the headlights on (running lights or headlights) my fuel guage drops to empty and my temp guage tops out. Turn the lights off and they go back to normal. When i turn my turn signals on all the guages bounce (minus speedo).

I know alot of light issues can be fixed with a new light switch or if it has a floor dimmer, the dimmer on this is in the column, and i plan on getting a new headlight switch on payday (even if it doesnt need changed its a cheap part to replace)

Any suggestions on what it could be?

Usually that is from a ground problem, if it just started without you doing any work on it recently I would look for obvious grounds broken in the engine compartment.

 

[warrpath4x4]

Usually that is from a ground problem, if it just started without you doing any work on it recently I would look for obvious grounds broken in the engine compartment.

unfortunatley i just picked it up and its been there since i got it, i will look for ground issues this weekend though, thanks

 

[496truck]

Remove the cluster and check the plug that goes into it. It's a big flat connector that basically clicks on to the printed circuit on the back of the cluster. Where those connections meet it can get fuzzy/corroded and create all kinds of weird things. Try cleaning the connections and bending tabs to make a tighter connection. Heck, last time I had mine out to replace bulbs I didn't click the plug back in all the way and it was doing stuff just like you described. Took it apart, plugged it in better and it's been good.

Always check the simple things first.

 

[warrpath4x4]

i need to replace some dash bulbs anyways so thats a good idea