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I recently posted a thread about how my driver's side tail light won't get brighter, as when you'd step on the brake or use the turn signal. Well now it's even more confusing.
I tested the continuity of the bulb, both filaments are fine. And yes I have replaced the bulb with another one just to be sure. I checked the voltage first at the wiring harness near the steering column, 12 volts on the brown wire (parking lights), then 12 volts on the yellow wire (turn signal for the left) and 12 volts on the green (I think?) wire (turn signal for the right). Then I checked it at the connector where you plug the bulb in, 12 volts each connector. But still for some reason it doesn't light the bulb up. Has anybody had any kind of experience with this or do I just need to stick a flashlight in there and switch it on and off myself?
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
i'm almost sure you have a ground path that is screwed up... if the bulb cannot find the proper ground path it will be creative in making its own ... so ,since the dual filament bulb shares a common ground if that ground is not working the electricity will try to go through the other filament and try and find a ground....causing all sorts of wierd symptoms. try groundiing the socket with a wire stripped and wrapped around the base of the bulb inserted into the socket and connect that to a known good ground (such as the battery). if that fixes the problem then you know you have a ground issue
Last edited by bobs77vet; Oct 12, 2004 at 11:27 AM.
Better yet...use a test light that you know is grounded properly and test out both contacts in the light socket. This will quickly tell you if you have fire to those socket contacts.
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
reference your quote "Then I checked it at the connector where you plug the bulb in, 12 volts each connector. But still for some reason it doesn't light the bulb up."
In light of the last post ...which got me thinking... to get the referenced 12 v reading where did you ground the voltmeter to?????
on my 79, i had some dim rear light issues,cleaned the area where the ground wire hits the frame, put some no ox grease on it, screwed it back down, end of problem.
reference your quote "Then I checked it at the connector where you plug the bulb in, 12 volts each connector. But still for some reason it doesn't light the bulb up."
In light of the last post ...which got me thinking... to get the referenced 12 v reading where did you ground the voltmeter to?????
When I checked the wiring harness, I used another grounding wire attached to the frame. When I checked the connector for the bulb, I used the ground inside the connector. Maybe I Just need to clean them.
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Originally Posted by Enkil
When I checked the wiring harness, I used another grounding wire attached to the frame. When I checked the connector for the bulb, I used the ground inside the connector. Maybe I Just need to clean them.
lets us know if cleaning the ground inside the socket worked? I suspect it will. it could have been that the points of the multi meter penetrated through the oxidation where the bulb socket doesn't.
I had the same issue for months on the 78. I ran extra ground wires to be sure that was not the problem. Turned out, on the steering column, the big long harness plug had some corrosion on the terminals. I cleaned those and it has worked perfect since. I hate elec. problems, good luck,,,,,,,,,,,,randy