I need help fast! I have to drive this truck to school on monday. I pulled the dashpad off to remove my A/C vents as I don't need them anymore and plus to make it easier to change the headlight switch whitch isn't working. Here is wherr my problem starts. I have the dash apart to fix the headlight problem. Everything would work except the headlights. Now that the dash is apart and they gave me the wrong switch so I put the old one back on. Now anytime I hit the brakes the driver side blinker comes on along with the blinker light on the gauge cluster, and the brake lights. The blinkers do not come on at all with the blinker switch. Any ideas?

 

This could be a lot of things... shorted/crossed wires (can happen when they melt at the headlight switch), failing turn signal switch are the first things to come to mind.

But I'm making a lot of assumptions as to the condition of everything....

 

Also check your bulbs.

 

To me, sounds like a ground problem with the dash.

 

I as getting ready to agree with the above, but the more I think about it, the more I think it might be a problem at the rear tailight grounds.

He says he has a problem when he hits the brake pedal. The cluster doesn't have any lights or anything to do with the brake power.

If he turned the headlights on, and the dash cluster turn light lit up dimly, then I would agree it is probably a cluster ground, since the headlight switch sends power to the cluster lights, and the turn light is up there also. And they both use the same common ground wire.

But if it's related to the brakes, I am thinking a rear tailight ground problem is causing it.

 

If I'm reading it right, all he really did is change the headlight switch (and put back the original) when this problem began... this makes me suspect melted wires at the switch that have been disturbed but that's with a lot of assumptions being made...