GM (and other OEMs) Light Bulb Socket Issues.

Messages
2,457
Location
Toronto, Canada
I noticed the DRLs weren't working anymore, so I pulled the 4114K bulbs(similar to 3157 but of higher wattage and longer life) out and put in new ones and the DRLs are working again. However the old bulbs passed the multimeter test for continuity on both filaments and they light up (thick filament) when I apply 12V to it. I likely have arcing corrosion on the socket contacts and perhaps a bit of fretting corrosion. I expect the new bulbs might not stay lit for long before arcing corrosion reappears. If I replace the sockets I will likely expect the same corrosion a few years hence. I am going to replace the 4114k bulbs with led equivalents and not bother replacing the existing sockets. The 1/2 amp draw vs 2.15A draw should go a long way in preventing further arcing damage. Exact same thing happened with my rear brake lights a few years ago. I had no brake lights but the bulbs worked when powered up without the sockets. I replaced the bulbs with leds and have had no further problems since. It seems to me that the miniaturised sockets cannot handle their design currents well. The old 1157 sockets could handle currents better than the later 3157 sockets.
 
Messages
11,384
Location
Phoenix
I always put a tiny dab of dielectric grease in the socket when I replace bulbs and it seems to ward off any problems with corrosion.
 

Nick1994

$50 Site Donor
Messages
13,323
Location
Phoenix, AZ
Drive around town and look at that model of Chevy trucks, almost every single time you see one, there's a DRL burned out.
 

George7941

Thread starter
Messages
2,457
Location
Toronto, Canada
It is not weather-related corrosion since the socket seems well protected with a nice rubber seal. I doubt DeOxit or dielectric grease is going to help with arcing damage. Seems to me the issue is the socket contacts just cannot handle the current.
 
Messages
238
Location
NY
The fixtures are not designed for LED bulbs and no LED bulbs have been developed as a safe substitute, sorry to say. A heavy duty socket is available and should have been used at the factory. It is shocking to see how poor quality sockets are used.
 
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Messages
36,475
Location
ME
My bayonet base brake/tail sockets lost any sort of spring tension. I have 1/2 a cubic centimeter of that earwax grease from each bulb if anyone wants me to mail them a packet. LOL It worked well-- no corrosion! Cure was to get a bendy pick under the base connections and yank 'em upwards.
 

George7941

Thread starter
Messages
2,457
Location
Toronto, Canada
Originally Posted By: eljefino
My bayonet base brake/tail sockets lost any sort of spring tension. I have 1/2 a cubic centimeter of that earwax grease from each bulb if anyone wants me to mail them a packet. LOL It worked well-- no corrosion! Cure was to get a bendy pick under the base connections and yank 'em upwards.
Ordinary household 120V medium screw base bulb sockets can also be similarly restored by pulling up on the centre contact but the fix never seems to be permanent. Once the centre contact is bent it never exerts the same tension and I end up having to eventually replace the entire socket.
 
Messages
8,598
Location
Florida
Some wedge based sockets last, some don't. I'm convinced it is a simple quality control issue. Also, for some reason those sockets fail on GM cars first.
 
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