WARNING - H3 Off Road Lights - Possible Fire Hazard

[evldave]

Originally Posted by H3.007

Hi All,

Recently, I accidently bumped the off-road light switch in my H3 without realizing it. I began smelling burnt plastic about 15 minutes after I fgure I had bumped the switch but did not realize what was "burning" until I noticed my lamp covers warping about an hour after I figured bumped the switch.

Been there, done that. Melted the plastic covers right into the lens. It was one of those black plastic toggle switches. I switched to lighted aircraft style (w/o the interlock) so now I know when they are on. We all make mistakes.

Originally Posted by H3.007

The Hummer dealer I bought the H3 from had installed the off-road lights post shipment. When I told them about the problem, they allegedly checked the GM specs for the installation and they said they did it correctly - but were willing to replace the damaged items and rewire the switch to the ignition relay.

I checked the FSM - Roof Mounted Off-road lights are wired HOT full time straight from the fusebox. Instructions to install are cake. I'm guessing the installation was done per spec.

Originally Posted by H3.007

I have been wiring vehicle electronics for close to fifteen years now and I have never heard of wiring a push button switch to a "hot wire".

Now you have...

Originally Posted by H3.007

Does anyone else have an H3 with the hot-wired botton? Do any of the Hummer techs that frequent this site know if it is a common practice to do this or not?

Based on what I see, I'm hoping everyone does. I don't know where you come from, but all my offroad lights are wired full-time hot so I can have them on at night without having to start the truck (and hope I don't wear down the battery)

Originally Posted by H3.007

If it is - fair warning - I bet there's a decent chance that the melt could result in a fire that could burn the vehicle, house, or garage the hicle was stored in if not caught in time. Thankfully, I was there to realise the problem. But I wonder what would happen if the problem was left unattended overnight???

I completely disagree with this. The ignition temperature of most metals (what your truck is made with) is higher than what the light will get. The ignition temperature of the plastic (is it ABS, I don't have one) is also likely much higher than the lights will get.

Most likely scenario for when people forget and leave their covers on is the plastic melts and stinks. If you aren't around, the temps will get high enough to most likely melt the wiring of lights, causing a short and cutting power (and no more melting!). Most wiring is rated 90-105C, which is much lower than the ignition temps of most plastics, so the insulation melts first, before there's a fire.