High beams off with truck on

High beams on and cluster works
Having some trouble with my blazer oddly the cluster and radio and inside light only work when I put the high beams on and if I have the radio on and all the light inside turned on it starts sputtering weird never seen this problem any help would be appreciated

 

Welcome to the forum. What year is your truck?

George

 

Quick guess issue is in the multifunction wiring or body control module. With those radio controls on steering wheel I lean toward multifunction seeing you state radio operation effected too. Wonder what it does in flash to pass? Really not enough info yet to give a better idea.

 

If you will provide the year of your vehicle I can offer an analytical approach to reading the electrical diagrams and diagnosing your problem. It will require you to measure voltages, pull fuses, and report results. Let me know if you would like too do that. Others will offer you their best guess at parts replacement which is another, and the more common approach.

George

 

I was thinking multifunction, also, just from hearing about it on here for so long. Never had an issue with mine, knock on wood. Definitely something for OP to research into

This would be the best bet, OP. More time consuming, but much easier on the wallet vs throwing money at it and seeing what sticks! Lol

 

My truck is 98 thanks for the response I’m currently replacing the turn signal switch . Maybe that can be a problem but I feel it’s not grounding I was thinking about giving a quick test grounding the negative to the body and seeing if I have a short somewhere . Yea it turns on fine sometimes it works but most times I have to hold the high beams in order for the cluster and radio also the heater to work

 

Heater too? Sounds almost like a bad ground to chassis. What the high beams have to do with it is certainly odd. Thing is all those features run thru the BCM. I’d check the connectors on it, fairly easy to do. The follow the harness to over near brake switch (basically base of steering wheel) and look that over. The point it does work at times implys bad connection more likely than a failure of a part.

 

I’m on standby if you want to analyze your problem to determine the fix quickly and try to save some money, just let me know.

The headlights have common power wiring and fuses with the gauges and switches and that’s where an analytical approach comes in. If you prefer to swap parts then the MF switch is as good a guess as any but it may be more complicated than that. Report back.


George