200S Envoy low beem lights going out

[kick-back]

I have a 2004 Envoy that the low beem lights began to work intermittently then went out last night. The high beem lights were used with no problems. The low beems began to work later. I will check all connections and fuse and fuse block connections today. Does anyone else have any ideas. Thanks

[maxwedge]

Welcome to AF. Check for 12v at lamps when out, then check the relay then back to the switch.

[fishhead65]

I have this same problem on my 2003 on one side. Changed the lamps and still does not work all the time.

It only works when I turn the swith on and off once or twice, it will not work when they come on automatically at dark.

Sounds like it could be the switch?

socket looks good, wires look good.

Where is the relay?

[maxwedge]

The relay would affect both, it is in the under hood power center, r/s of engine compt.

[fishhead65]

so if only eeffecting 1 side then can I elimininate both the relay and the switch?

If so that would leave only the socket and the wire run, right?

[maxwedge]

The right way to attack this is with a comprehensive wiring diagram, tracing the dead side wiring back to it's 12v source is the way, also check grounds in the circuit.

[envoyxuv]

Also be aware that the low beam headlights on your envoy are powered by what is called a headlamp driver module. It's located in the fuse block on the left (driver's) side under the hood. It's black and resembles a relay, but is abbreviated: HDM. The purpose of this driver module is to allow the body control computer to control the daytime running lamps. It sends a pulse width signal that operates the headlamps at a reduced intensity (about 85% of normal low beam intensity).The fan clutch uses the exact same driver, and is also located in that fuse block- back to back with the HDM. This is not a mechanical relay, but a solid state (no moving parts/cannot be disassembled) relay. You may want to try swapping the two to see if anything changes. The underside of the fuse box cover lists the two as solid state relays; FAN and HDM.

[BRD]

Reason I ask, I just replaced the low on the pass side of wife's '03. OEM was a Philips. The parts house had a variety of 9006 bulbs as to brand, color, intensity, etc. I went with a Wagner OEM clone ($10 so I picked up a spare for when the driver's side goes south), which the guy at the counter said they're getting longer service out of than Sylvania (higher $) or the O'Reilly's house brand ($1 cheaper). It seems to be working just like it should. I pass this along FWIW.