keep melting headlight plugs [Archive] - Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum

: keep melting headlight plugs


tomas216
03-11-2009, 03:27 PM
where does the ground wire end up on the low beam headlight? ive got a 03 envoy and ive been melting the headlight plug on both sides about once a month. im thinking that they use the same ground and it is loose, causing a spike in voltage and eventually melting the plastic connector. am i way off? anybody have similar experience?
thanks

the roadie
03-11-2009, 03:40 PM
The left and right headlamps don't share a common ground. They're separate. High and low beam grounds are spliced together inside the harness.

But a loose ground would cause a LOWERED voltage at the lamp because the vehicle's 12-14V isn't going to change. So the ground lug would see increased heat and could be damaged, but if anything it would reduce the amount of stresss on the headlamp connector.

Are you running OEM lamps or aftermarket ones that draw more current? Silverstars are notorious for smoking the OEM connectors. But the OEM connectors are lightweight anyway. One trick is to apply some bulb grease to at least keep air out and that may reduce oxidation and keep the contact resistance down and reduce heat build-up.

tomas216
03-11-2009, 03:50 PM
ive tried different bulbs. right now im running the plain ge bulbs that come in a yellow package. i use to run a higher priced sylvania clears bulb. either way i melt plugs. i dont think i have any corrosion in there right now, both plugs are brand new (seeing they get replaced every month) and both bulbs are new last week. i thought maybe if the ground was loose that the voltage would be turning off and on rapidly causing heat in that plug.

the roadie
03-11-2009, 03:56 PM
Heat doesn't come from a rapid on/off at those frequencies. It's actually the way that our DRL function works. The vehicle pulses the low beam lamp at a speed that they eye can't see, but it's off a lot of the time so it's not at full intensity. I'd try the bulb grease as an experiment and sandpaper the bulb contacts a tiny bit before installation to remove any oxidation from their storage time.

tomas216
03-11-2009, 04:20 PM
sounds good, i'll try it out. thanks for the tip

10856
03-11-2009, 04:29 PM
I had the same problem for a couple years until I started using the dielectric grease and I also slightly bend one of the prongs on each bulb in about a 1/16th of an inch to make a firmer contact, I think heat is generated from arcing current at the connection and those sockets oem and aftermarket are no match for it and just fry, good luck

ktacer
07-06-2009, 10:53 PM
Where do you find the aftermarket plugs? I have a 2004 trailblazer that just melted the low beam plug.
thanks,
Ktacer

MajesticLT03
07-06-2009, 10:59 PM
Where do you find the aftermarket plugs? I have a 2004 trailblazer that just melted the low beam plug.
thanks,
Ktacer

Autozone

AbsoluteZero
07-07-2009, 09:18 AM
Another vote for bulb grease...
haven't had a burnt socket in over 3 yrs

speer12614
07-08-2009, 04:44 PM
hi all,

new to the forum here. i have an 02 trailblazer and the low beam on the driver's side went out last week. went to replace the bulb and found the plug melted. finally able to get a replacement plug. after taking a look at the situation, i'm not sure i'm supposed to take the back off of the lighting assembly to change the plug or what.

i noticed that obviously many of you have replaced the plugs and whatnot, and this is the first time mine has melted in the four years i've owned it, so i'm not looking for some complicated fix. just replacing the plug. any pointers?

AbsoluteZero
07-09-2009, 08:50 AM
hi all,
i noticed that obviously many of you have replaced the plugs and whatnot, and this is the first time mine has melted in the four years i've owned it, so i'm not looking for some complicated fix. just replacing the plug. any pointers?

The short answer is just cut out the melted and splice in the new....
One of my socket was replaced under warranty. They just cut off the old socket and used crimp-connectors and installed replacement. HOWEVER my preferred method is to solder the new connector in place using shrink tubing as the insulator. The crimp connectors haven't given me any problem but I did dab some liquid insulation in the ends.
I'm sure you know not to touch the bulb with bare fingers.... skin oil shortens it's life.

klaliberty
09-28-2009, 05:14 PM
For the low beam headlight plug? I need to get my wifes fixed :)

tomas216
09-28-2009, 07:47 PM
low beam headlight is 9006 and the plug will say 9006 somewhere on the packaging.

http://www.amazon.com/gp/product/B000TTCVYU/ref=pd_lpo_k2_dp_sr_1?pf_rd_p=486539851&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B0014JDFJO&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=0Y1ZNCWA5RENMV51T6XM

LovemyEXTLT
12-13-2009, 07:40 PM
You all know the song "bit once, twice shy baby"... The first one I didnt mind so much... easy fix yet thought it was a little odd. This is the second time I've had to replace the same sides plug. I just tested the fuse box where it says that sides(passenger side) fuse is and its not blown but the curcuit says it is getting the power through it. What is the FIX not the band-aid for this issue? If the entire one side of the plug wasn't melted to nothing and smells like burnt what not I wouldn't be so worried about it... but with that and the fact that this is my wifes vehicle that she is often hauling my son around and more often hauling friends and family around... I'm a little worried about a fire starting. Anyone know what might be the cause of it melting and not breaking the fuse?

Thanks for your help!

tomas216
12-13-2009, 07:53 PM
i bet you've got a bad ground to your headlights, thats what my problem was. so buy a new plug, actually buy two new plugs so you can fix both sides, and when you connect the two wires, connect the power just like you did before, but connect the ground to your chassis, i drilled a hole to some metal in the engine compartment and bolted it to that. cured it! last year i went through 10 plug harnesses, this year, none!

the roadie
12-13-2009, 07:54 PM
The cause is heat build-up in the socket caused by the current flow. The lamp is a 55 Watt bulb, but if there's any slight oxidation in the socket or lamp contacts, then instead of delivering all 55W to the lamp, some of it gets wasted in socket contacts. Let's say 2 Watts at first, leaving 53 for the lamp. That heats up the socket a bit more than a perfect socket, and then when you turn off the vehicle, the metal contacts shrink, touch the lamp wiring in a smaller area, and some oxidation forms, increasing the resistance of the socket->lamp connection. So next time the increased resistance causes more power stealing, and the socket then swipes 3 W, and only delivers 52 to the lamp. 3 Watts heats up the socket more than 2 Watts, so the effect gets worse over time. Eventually, the socket is stealing 10 Watts and that starts dimming the headlight and melting the socket.

Only cure is to prevent oxidation by using bulb grease in the socket to exclude air, especially moist air, using a better socket design with more spring force on the contacts, gold plated contacts (I haven't seen these for headlights, but somebody probably makes 'em, or start with perfectly clean and polished lamp/socket contacts that don't steal even 2 Watts at the beginning so they don't have any tendency to heat up at all and start the vicious cycle.

LovemyEXTLT
12-13-2009, 08:00 PM
buy a new plug, actually buy two new plugs so you can fix both sides, and when you connect the two wires, connect the power just like you did before, but connect the ground to your chassis, i drilled a hole to some metal in the engine compartment and bolted it to that. cured it! last year i went through 10 plug harnesses, this year, none!

How do I know which one is the neg. and which one is the pos.? I have a circuit tester (bought for just this reason tonight). Didn't even know there is a such thing as bulb grease... note to self next time I dry by the parts store....

Robert1101
12-13-2009, 08:12 PM
If you want to get around oxidation and the related headaches wire the bulb in without the socket. I have 5 years on my bulbs and no problems... however before I had nothing but headaches. Ended up bending the contacts in the socket a lot and then pushing in the bulbs. All is very firm..... Running silver stars. Anybody running the toshiba bulbs? (john deer HIR 9011, HIR 9012?)

MichEnvoyBoy
12-13-2009, 08:32 PM
When I bought my 2002 Envoy (used) in 2004, my drivers side headlight was burnt out. I went and bought a replacement bulb at AutoZone.

When I took the old bulb out, I found a totally charred and melted plug. I replaced it with a new one, and a week later it burnt that one too. To top it off - my passenger side went out and I discovered it was a charred plug too!!

This went on for 2 more times, and finally it stopped. I put regular ol' sylvania 9006 bulb in - not silverstars, and silverstars werent in there to begin with - the only thing I can see that changed was I got a new battery, and after I installed the new battery the melting plugs stopped. I still dont know if it was coincidence or what... but it hasnt melted a plug since 2004!

drkblaze
12-16-2009, 05:26 PM
i just blew my first drivers side low beam this week. i sat on it for about two days and just went to replace it yesterday. i pulled the battery to get easier access. i installed my new plug, put the battery back in. started the car, light works fine

heres the catch, now my radio and hvac remain powered once the vehicle is shutdown and exited

what am i to do?

Stripes
05-27-2010, 03:28 PM
I have just melted a connector on the passenger side low beam..

Is their a specific brand of OEM or aftermarket replacement that is a better quality plug?

Thnks
Stripes

Pained
09-27-2010, 04:41 PM
well i was going to install my HID lights today but when i was tearing everything apart i noticed my pass. side headlight plug was shorted out does anyone know if these http://www.autozone.com/autozone/accessories/Painless-Wiring-Headlight-plug/_/N-2691?counter=0&filterByKeyWord=headlight+plug&fromString=search&itemIdentifier=196472_0_0_ will work with out TB, its the only one i can find that autozone sells or any store that is nearby. could someone plz type a link to one that would work if that one doesn't, thanks

-Pained

shoe780
10-14-2010, 11:44 PM
http://www.dormanproducts.com/p-18621-84793.aspx

LovemyEXTLT
12-18-2010, 11:37 AM
Ok, I finally went all out and said F it! I'm going to fix this or at least make it easier on myself if it does it again. (I fixed this issue months ago but forgot about this post until today) I went to the local parts store and bought some extra wire, bulbs for both sides and an inline fuse unit for both sides. I put the new bulbs into the new harness and wired the inline fuse unit with fuse (duh) and ran the ground to a bult near the headlight area (can't remember exactly what it was I used now) and it has yet to burn a single bulb yet and its been months! if not a year by now. Oh, I also used wire nuts to make it easier to install a new one in the future (crossing fingers that never comes, so far so good).

Time it took... after beers, BS-ing with buddies while doing it and the actual fix... few hours.... exclude the extras.... about an hour each side due to tight fit/area (I didn't take the hole headlight case out for this).

Good luck to all you out there with this issue!

tomas216
12-18-2010, 08:48 PM
what solved my headlight melting problem was to relocate the ground. i bought two new headlight plugs, and hooked the power wire up to the old power wire, but on the ground, i crimped a ground loop on the end of it and bolted it to the frame just above the headlight.
headlights blown:
2009- 12
2010 - 0!!

pdt507
12-19-2010, 03:21 PM
Has anyone tried the ceramic plugs? I found this set on Ebay. http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=140477700625&viewitem=&sspagename=STRK%3AMEWAX%3AIT Curious if they would work or not. My plugs burnt years ago but I never replaced them. Been running Silverstars for about 4 years and haven't had them go out due to the plugs, just the stupid DRLs which I recently fixed with a DRL killer.