ZR2 Quad Beam Mod Mistake

Please help! I tried to do the quad beam mod and messed up my headlights. I have a 2000 GMC Sonoma SLS Highrider with low beam DRL's and AHL. I tried to ground the purple wire on the bright beam driver's side headlight. Didn't work. So I moved the ground to the other high beam wire. Didn't work. Then I moved the ground to the yellow wire on the low beam. Didn't work. Finally I moved the ground to the other wire on the low beam. Didn't work. Frustrated I just put everything back like it was before I touched it. Now the driver's side high and low just barely burn. Passenger side has full power on high beam and full power on low beam but on high, the low burns slightly. On low, the high burns slightly. Please help me either do the mod right or fix it back the way it was! :banghead:

I would start with checking grounds.
And if you have cut or spliced wires make sure all connections are soldered and sealer applied and heat shrink tubing.

Did you read the instructions on the mod all of the way threw about 3 times and make sure the mod applies to your truck/car?

Thanks I'll try checking the grounds. I did not solder but I used heat shrink butt connectors to reconnect all the wires.

Thanks. Yes and I really thought it was going to work. Apparently I need to use the relay method. But I'm wondering why they won't work correctly now since I put the wires back the way they were. Going to check the ground block under the air box. Maybe I pulled something loose.?.

Thanks I'll try checking the grounds. I did not solder but I used heat shrink butt connectors to reconnect all the wires.

Butt connectors are not a 100%
Soldor is best.
Also if you have a volt/meter or good test light thes for good voltage to headlights.
Let us know how it goes.

Thanks. I'll let you know. (May be a few days before I can get back on it though). Working a lot. But thanks for the advice.

....I have a 2000 GMC Sonoma SLS Highrider with low beam DRL's and AHL....


Keep in mind, the DRL's use the high beam filaments at a reduced voltage. The circuits that control the high and low beam headlamps, DRL's, flash to pass, and Auto lamp, use relays: some switch ground, some switch positive. None of the wires at any of the headlamps go directly to ground.
As MT said, get it all back to original with good connections.


What exactly are you trying to do?

I was trying to make all four lights shine with the bright lights on. I must have shorted something in the process. If none of the wires go to ground originally could my current problem indicate I burnt one or more of the four wires or the relay? I plan on testing the voltage on all four wires tomorrow as well checking the ground block under the air box in case I messed something up there. I'll post the results.

Is the vehicle equipped with the ZR2 option? Look on the sticker in the glovebox for the 3 character RPO code. Headlamps are wired differently with and without the ZR2 option. If the RPO code sticker is not attached to the glovebox door, post the complete VIN and I will look it up.

Fixed it! It was a blown fuse. Left headlamp fuse under the hood. Can't believe it was that simple. Yes my truck is a ZR2. Thanks a lot guys for the help! Going to find the ZR2 instructions for the quad beam mod now! Will post if successful.

You'll want to tap into the driver side yellow wire and ground it. Are you just wanting to do the quad beam mod, or are you wanting to disable DRL and/or AHL, too?

Also, if you want more light, I highly recommend the HIR 9011 bulbs. They replace the normal high beam bulbs and throw a lot of light.

It worked! Grounded the yellow wire and now I have all four lights going on bright. Thanks for the tip on the HIR 9011 bulbs too. For now I don't want to disable the DRL's or AHL. Maybe another time. Read that the setup's got to change for the quad beam if you want to disable DRL. Another day.