headlight dimmer relay issue

I have a 2004 prerunner and have a dimmer relay issue. I have no bright lights, I changed the dimmer relay and everything was good - for 1 1/2 days. no bight lights again. I changed out the headlight switch prior to see if it was bad and it was no different. I replaced the original headlight switch and put new relay in, worked for the day or about 5-8 tests.
Any ideas on this problem?
Poppahank

 

Do you have any non OEM lights? If you are burning up the relay it could be because you are pulling too much current through it... Could be a bad ground, something causing either a short or an open somewhere. Get a multimeter and start testing things.

 

no after market additions. I checked lights, and power to plug. Any hints on testing the ground on this plug or relay plug would help. All fuses are good.

 

I don't have a wiring diagram, maybe someone else can jump in to help with that. Basically you want to test each connection starting with the most likely cause or follow the flow of electricity from the fuse box to ground.