Hello all,

I went to install some Holley LED headlights in my 1986 4Runner DLX and am having some issues. The same issues occurred with the prior cheap LED eBay headlights that the prior owner had installed. I thought it was the headlights themselves but that does not seem to be the case.

Low beam works. Low beam signal is 13V+. When you switch to high beam, the lights dim A LOT. No flickering, just dim. ~8V is going to the low beam signal and -5V is going to the high beam. Headlight relay sounds like it works fine (switches on when you turn on the headlights).

My best guess is that there is a short in the combo switch. Does anybody else have any other ideas / suggestions OR has had this issue before?

Thanks!
Franklin

 

This harness may be for a dual headlight system not quad. Maybe you need a second wiring harness to trigger the other 2 lights, my best guess on this.

 

This is a known condition with LED lights in some vehicles, and not exclusive to just Toyota.
Some retailors on Amazon offer a harness that adapts the LED to your electrical system.

The company that made your bulbs should offer a kit, but you can find them easily on Amazon, too.

 

Yeah, Holley stated they were "plug and play" but do not think that is true. I believe the harness here will fix the issue:
This Holley harness will as well: Holley H840 Holley RetroBright switched ground harness

A guide to install is here: 1st Gen 4Runner H4 Headlight Conversion • My Off Road Radio

I'll let everyone know if this fixes it.

Thanks!