Help with LED/headlamps...

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Help with LED/headlamps...

Post by Angmar » Sat Oct 05, 2019 12:56 pm

Hey guys, having a weird issue with my LED headlights (one actually). The passenger's side keeps burning out. I think that it may be a wiring issue but would like to hear from some of the more experienced electrical guys on this one.


Car has a mag and battery but I run the headlamps off of a small 12v battery that is wired into the system like a normal battery would be, mag is not in that circuit. The correct loom comes up the passenger side of the engine compartment toward the passengers side headlamp as it should. In the loom one wire (hot) runs to one of the terminals on the back of both headlamps. Each headlamp has wires running from the remaining terminals to the frame for grounding.

The driver's side lamp will run for hours with no issue. The passengers side will work for a short while, eventually flashing on and off before it goes out completely. I did notice an odor of electrical burning in and around the headlamp area. I have checked the socket and there is power to one of the terminals and the socket housing seems to be grounded and working.

What am I missing here?

thanks for you help and suggestions.
Still crankin old iron

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Wiring problem ?

Post by Novice » Sun Oct 06, 2019 11:29 am

What year is Your car. Have the Led headlights been working or is this a new installation. on 1919-1927 cars one wire from each light should be going to dim terminals on the terminal block / switch. the other wire from each light to the ON terminals / switch. with the ground connection to the light can going to the car frame. If one socket wire is grounded sounds like You may be using LEDs that have one tab positive and the other negative and light base has no connection. Does Your wiring harness / loom have two headlight wires. Even if there is a bad connection the LED should not burn out unless there is too much voltage on it or the polarity is reversed in which case You may get one short flash maybe and its RIP LED. Sounds like You have several problems. To start one headlight socket wire being grounded does not sound like original wiring. sounds like wiring modifications have been made. I would put the wiring back to factory specs unless magneto lights and start over with the proper led replacements. which now include some very good six volt led headlights which do not need a extra battery and problems associated with keeping it charged.

Good Luck

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