Low beam went out but high beams work and all running and tail lights work.
I've checked all fuses and relays still nothing.
It's been to the dealership and also to a electrical shop and nobody has a clue.
I pulled the dash apart, tested the dash switch and the steering column switch both are working.
Traced wire out of the column switch down to connector-it's good.
Scanned the BCM it's checked out good.
Went the other way from the headlights back to the fuse box under hood (distribution box) all wires checked out good. Unplugged wires from the distribution box and ran power plus ground and lights will work.
Really need good color wiring dia. for a ZR2 - the one from alldata doesn't help the colors don't match.
any advice ?
Thanks
Big K

 

If you have a subscription to Alldata, report the discrepancy. Their diagrams typically cover the regular s-series which the DRLs on the ZR2 do not match what is used on the rest of the s-series vehicles. That doesn't mean that they cannot correct the problem.

You should have a DRL relay that controls the operation of the low beams instead of a combination of relays that the rest of the s-series trucks have that control the high beams either in parallel or series (DRL & regular operation respectively). This relay simply controls power to the low beams regardless of the position of the switch. If the relay were to fail completely open, the low beams would not work.

 

I have changed relays around, swapped one out at a time still nothing.
I can hear the relay on the hdrl working plus I tested the relays with a meter and power and ground.
The Alldata dia. I got was from the dealership.
Just looking for a better one.
Getting a copy of Mitchell to see if it is any better.
Big K

 

I have access to both. No difference in diagrams from Alldata and from Mitchell1.

Can you determine if it is a power or ground issue at the headlight plug? I would assume that it is a power issue if you can supply power to it and have it work.

 

It's a power issue.
Thanks for letting know about Mitchell.
I've got most of the color figured out.
I'll keep looking Haven't given up yet!
Thanks Again.
Big K

 

you might check the park/brk pedal to see if it's returned all the way. (broken,rusted up) don't know if 02's are the same, but my 98 has DRL's and when you apply the p/brk it cancels the DRL's, when i released the P/ brk i had no low beams even using h/lite swt. why they ran it through the p/brk instead of a dash swt or something i'll never know, i took off the lwr dash pnl. and there's some serious big wires to the lever assy. worked the lever back and forth, checked for pwr everywhere same as you did. spent all afternoon THEN just for s11ts and giggles i looked in the owners man. this has a auto sensor on the rt dash spkr and when i pulled in the garage it sensed darkness and poof, all my lights came on. so i put it all back together and backed it outside and everything works like it should. so far,i don't know if i fixed anything or not. but i'm still eyeing the p/brk assy.

 

I checked the parking brake single wire on the bottom but didn't check the ones on top.
I'll check those next maybe that will work .
Thanks
Big K

 

Well I have found the problem. It wasn't the parking brake it was in the distribution block under the hood.
Traced all the wire back and found the signal wire from the Body control module(yellow wire #4 pin plug closest to the firewall) was burnt going into the distribution block. Fixed that and now all lights working correctly.
Thanks
Big K