High mount Brake light problem

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dfowler
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My High mount Brake lights seems to not work all of a sudden. At first it was just one bulb. I checked them, bulbs look fine. Now both isnt working. I tried to use Dielectric grease on the connecters. Could this be the problem or should I just try brand new bulbs?


maxnix
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Try some Sylvania LL bulbs. If that doesn't cure it, time to look at the wiring and sockets, then the control unit.

Q45tech
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Failure to replace bulbs as they age and draw more current melts sockets, reflectors, and the solder connections in lamp diagnostic module.

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dfowler
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I replaced them already and still no light. On my dash it says stop light out. Could it be the control unit. Where is it located? Im looking at the connecters now and they look fine. I dont know what else it could be.

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dfowler
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I noticed when I switched to the Long Life bulbs, plastic started to melt into the connecter and bulb but bulb still looks in tact.

maxnix
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You really need to inspect all your rear llight sockets, wiring into them and bulbs for non OEM non LL.

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Q45man1
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You can also check FSM EL-30 (tail/stop sensor check). The sensor module is located in the trunk area next to the trunk latch. I had the same problem before and I ended up replacing the module.

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dfowler
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Hey guys, as it turns out I had to replace the bulbs and get some bulb grease. Installed the bulbs with a lil grease and now its back to normal. Cost me $5 bucks but I got the problem solved. Thanx for yall help. Without you yall,I could be SOL.

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Bulb grease? What on earth is that?

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its in the blinker fluid and muffler bearing aisle...

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dfowler
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Actually, I bought the bulb grease at the counter when I checked out.

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dfowler
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Now that I think about it, the bulb grease was a good choice for me because the socket itself was a little charred and burned. I just hope that it keeps the plastic itself from melting on the bulbs themselves,which is probally what blew them out in the first place.

maxnix
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Non OEM or old bulbs caused too much current draw which caused the melting, unless the wiring or socket corroded on its own.

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dfowler
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Non OEM or old bulbs caused too much current draw which caused the melting is why I replaced them when I first got the car, but the Long Life bulbs is where I noticed that the plastic over the bulb melted onto the bulb. I think the bulb grease will work to keep the plastic from melting.

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goody90q45
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dfowler wrote:Actually, I bought the bulb grease at the counter when I checked out.
I'm guessing the bulb grease must be a dielectric grease. Did it burn through the female sockets to the wires or is that end still intact?

maxnix
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I guess my question is if it is dielectric grease, then won't it short at some low level?

qship96
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maxnix wrote:I guess my question is if it is dielectric grease, then won't it short at some low level?
Actually, it is the opposite dielectric grease is NON conductive, so I am concerned it would inhibit good solid electrical connections between bulb and base contacts?

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goody90q45
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You're right. That's sort of why I brought it up. I put dielectric grease on a socket with corrosion and the bulb quit working. Good to see there is something useful to purchase in the bulb grease aisle.

maxnix
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qship96 wrote:
Actually, it is the opposite dielectric grease is NON conductive, so I am concerned it would inhibit good solid electrical connections between bulb and base contacts?
OK. so why is it called bulb grease and what is its function?

qship96
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Good queation! I googled it, definitly lists bulb/sockets as one of the uses-guess it keeps the bulb from galling in the socket, but at what cost? I cant see why you would want an insulator between electrical contacts.

Reminds me of years ago when they would advise you to coat the tubular incandescant bulb for your aquarium hood with vaseline to prevent bulb from corroding in socket{but that was a wet/humid environment, unlike the inside of automotive tail lights}

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dfowler
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Yeah guys, I used dielectric grease when I first inspected the bulb and socket because of the burnt plastic on and around the bulb. One out of two lights, one came on before the dielectric grease was added. After the dielectric grease was added to both sockets and bulb, none of the lights worked. Thats when I first posted High mount Brake light problem. I wiped most of the dielectric grease off, bought new Long Life bulbs which is what I bought the first time I got the car. The sales clerk asked if I needed bulb grease, which is when I asked about the dielectric grease is the same. They said no, so I bought the grease which was only $1.00. After replacing the bulbs, then applied a small amount of grease to the base of the bulb itself, it started working again. Hopefully, this will keep the bulbs from burning the plastic around the bulbs and melting onto the bulbs itself. I will monitor the results and holla back with the results. I'll keep u posted. As for my theory, bulb grease works better than dielectric grease.

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Like the main tail lamp sockets the usual proccedure is to replace the ALL 3 socket assemblies when owner abuse* has melted or corroded them.

Failure to replace bulbs as they exceed operating hours and limits.

Waiting until certain bulbs to fail on their own and create an open circuit means an end of life sudden burst of heat.



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