Ziggie

Hello,

My friend asked me to look into his 2008 Impala, where the HI Beams are always on, he said he pulled bulbs as a worlaround.
As I am Electronics Technologist, I have no problem working on this, but it would be much easier if I had some information, like a wiring diagram.
I suspect that for this year/model there should be a module which takes care of that, I think it is either switch or module or wiring in the steering column, I am looking for any info I can get. Buddy is comming tomorow, so if someone can help with scan or that portion of diagram, or just the description, I would greatly appreciate.

Thanks,

Ziggie

EinST

Welcome to the forum. I'm sure your buddy already looked for the relay and didn't find one. The relays for the headlamps and fog lamps are built onto the underhood fuse block PCB and thus not serviceable. I guess that's one way to keep people from messing around with DRLs and such. If you really want to tackle this job, consider a subscription to online DIY sites like alldatadiy.com or eautorepair.net.

Ziggie

Thanks,


I think I will check with HAINES manual, if they have diagram.
Relays are on PCB thus non servicable, well that is what I do for living, I troubleshoot to the component level, with systems complexity not even comparable to what is in the car.
I had once some experience with wife's 2003 GMC Envoy, where under warranty they (twice) install a seal kit for the wiper module, and gues what, sometimes in 2007 the wipers failed, and when I took it apart, there was water damage, one leg of a relay was corroded off.
I had two optons, get new assy for $300.00, or replace the relay, clean the PCB and seal it properly.
I should never let them to install that "recall" kit in the first place, they only messed it up, by not putting the small seal correctly.
Now, when I went back to the dealer and show them the pictures, I had a feeling I was talking to the wall, they said for $600.00 they will fix the problem for me. So, for the $5.00 relay and half a day of my time, wipers still work fine.

Ziggie

EinST

Okay, then, it sounds like you know what you're doing. I don't like to encourage people playing with or modifying vehicle electronics. There's a chance that subtle damage gets introduced and becomes a headache, especially for the next owner. Good luck.

Ziggie

EinSt,

All is good now, We got the Haines manual, switch and circuit is the same like in my 03 Envoy, and I suspect for many GM model/years, there are fuses for each HI beam, which would have been easier to remove the 2 fuses rather than disconnectin at the lamp, to disable the HI beams.
I took the turn signal/combination swith out and apart, well, after cleaning and lubricating it almost worked. There was not much I could do to fix the switch, as the plastic streched and it wasn't making or braking the right contacts. That switch does all, wipers, signal, hazard, HI/LO beam and FTP (flash to pass). I said it almost worked, the Hi/Lo & FTP did not work right only when the right signal light was selected, when I put it together.
For the price of a new switch, $80.00, it was time for replacement and we were able to get it at local dealer.
So two things happen, fault is fixed and I learned a bit for the next time.

Ziggie

Ps. You do not need to remove the steering column if you have a short angle torx bit to remove one of the screws holding the switch. I was very aware to the fact that I was close to the airbag.

EinST

Congrats. Sounds like some excellent sleuthing. Always nice to hear of success stories. Thanks for the update.

Hawksy18

Hello, Im a police officer whith a take home chev. impla im in need to be able to hook a switch up to the lights on the car so i can black out when needed.

Is there anything i need to do so i dont hurt the rest of the car ?

Ziggie

This is very interesting question and you almost answered it yourself.
Electrical circuitry in the vehicle is subjected to many things, like vibration, moisture heat and cold etc, and as a genereal rule it is not a good idea, (actually it is very bad idea) to tamper with the original factory wiring. I would definitely advise you not to tamper with the stop lights, for what ever reason, unless you eventually want to be rearended, like when you forget to turn the stop lights on.
The modern vehicle electrical system is designed and build to help users, the lights will go on with remote door, light will stay on for a while to help you in or our from the car, DRL etc, so disabling all this with a simple switch is not that simple, possble yes of course, but not simple, and remember, it has to be done right, otherwise you might have problems, like the worse thing, the car burn down.
NOw being a police officer you probably have some knowledge how the police cruisers are wired, can you turn off all the lights in the cruser?
For the general population cars the best way is to read the vehicle manual and perhaps that might help you a bit, for example how to temporary disable DRL while idling and stopped, with parking brake.

Ziggie