Headlights go dark when I turn on hi beams

[dsmelfi]

Hi. I've upgraded my headlights (speaker 8700) and bought the upgraded headlight harness. Checked all the wiring and grounds are all good .. but when I turn the hi beams on, the lights turn off completely. Has anyone run into this? Centech harness was installed about a year ago... Thanks! Any ideas are most welcome!

 

[Slowleak]

Does the high beam indicator on the dash come on? If not, you may have a bad dimmer switch. Check the green/black wire coming out of the dimmer switch for power when the high beams are on.

 

[Speedrdr]

Had the same problem with my ‘72, except it was the other way and low beam didn’t work. Was a long two hour drive at night Felt a little sorry for the oncoming traffic. Took the 2nd new dimmer switche to correct problem…and this was with OEM lights.

Randy

 

[dsmelfi]

I also have a classic instruments cluster.. but yes. The indicator light does come on when I hit the switch. I'll check the wire tho

 

[Slowleak]

Sounds like you are getting power thru the dimmer switch. I would check the high beam relay in the upgraded harness. I had one go out in my harness from Tom’s.

 

[dsmelfi]

It was indeed the relay! Had some rust in there so I cleaned it up with a wire brush and they seem to be working! I'll have to order a new one but hopefully it will hold for a couple days. Thank you for the assist!!