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So I checked the voltage to my trunk light and everything is getting the 12V that it should get. However the bulb does not light up no matter which bulb I try.
Have you checked the latch? Isn't there a switch at the latch (or maybe a sensor) that gets triggered to off when the trunklid is closed. Not sure if there would be voltage if that switch was off but it's worth a shot.
At first, whenever I was converting to LED, the bulb flickered and shut off as I was pushing it in. Could it possibly be the housing itself ? Part number 34262-TK4-A01
At first, whenever I was converting to LED, the bulb flickered and shut off as I was pushing it in. Could it possibly be the housing itself ? Part number 34262-TK4-A01
I wouldn't commit to that yet, but it could be...
Inspect it, see if it's corroded or has a broken wire!!!
I flipped the bulb and it still did not light. I got a contact voltage tester and touched it with the positive end. The tester bulb lit up however whenever I touched the negative side, the actual trunk LED bulb lit up. What could it be?
I tested using different leds and the incandescent bulb. All do the same. They light up when I touch the negative to my voltage tester which I have attatched to the bottom latch
Perhaps (and most likely) the bulb always has 12v on one side and the ground is only applied when the trunk is opened. The ground connection is probably made from the switch mounted on the latch mechanism.
That switch is probably defective or dirty, or you pulled the wire off while working in the trunk.
likely it's just the wire on the harness just behind the socket is loose and not making a good connection: see the (dark blue/light blue) pair? if it's okay there, then you'll have to trace it back
Rick might be onto something regarding the trunk switch though.
likely it's just the wire on the harness just behind the socket is loose and not making a good connection: see the (dark blue/light blue) pair? if it's okay there, then you'll have to trace it back:
I agree, in my business, when repairing something that is broken, rule #1 is to check the last thing you touched. From the photo it looks like the light assembly can be unplugged from the connector. Check for a ground inside the connector, if you see the ground at that point then the light assembly must have something cracked or broken internally. Sometimes the pins inside the connector need to be pushed deeper into the connector before reconnecting to the light.
Like others have said...you obviously have a bad ground somewhere along the line, likely at or near the lamp socket. Get yourself a digital multi-meter. It will make troubleshooting a lot easier.
Stick your test probe into the backside of the 12V side and the ground side of the wire connector (while still plugged in) and see if you get the same result. If so, the fixture itself is fine and your issue is with the wiring somewhere prior to the fixture. If the LED does not light, then your issue is inside the fixture.
Oh crap... what do you know. Just ran into this yesterday... same exact thing is happening to me. I installed a LED (probably a cheap one)... it didn't come on, flipped it it worked. I put the cover plate back on, it turned off. Tried another bulb, it barley lit up. Put the OEM back on... nothing. It doesn't matter what bulb I put in it... it doesn't light up. I called it a night, and here I am today.
a fuse?
It can't be a fuse because you have 12v on one side of the light. You have already proven that you are missing the ground on the other side of the light,
I speculated that the ground was applied from a switch attached to the trunk latch mechanism. Have you checked this area for a wire, and ensured it hasn't been pulled off the switch,
But if the light always has 12v on one side, and it gets ground applied to the other side only when the trunk is opened your modification will keep the light on all the time.
Try this test. Apply the ground temporarily as you have already done In order to light the bulb. Now climb in the trunk and close it. If the light goes off then your solution will work. If it doesn't go off then back to the drawing board.
Yep. The light just stays on all the time. I disconnected it so it doesn't kill my battery just in case. Any other ideas? I can't really trace the ground back because everything is all hidden away behind the metal.
The trunk light is controlled by the trunk latch, otherwise it would be on all the time and drain the battery. Pull off the rear trunk panel and have a look at the wiring on the latching mechanism. My bet is the wires are fine, but rather the contacts inside the latching mechanism are dirty and/or corroded and therefore are not providing a ground to your light. You could try disassembling it and cleaning it (if that's even possible).
For reference, here is the grounding point for the lamp (left side of trunk). I doubt that sucker came loose.
It sounds like you have the actual wiring diagrams.
Can you confirm that
A) the "latch switch" completes the connection to the + voltage source,
OR
B) does the bulb always have 12v on one side and the switch completes the connection to ground?
If B is correct, the OP can pull the connector from the switch and short the two pins together. If the light comes on then the switch itself is defective. If the light doesn't come on, then there is a break in the wiring which is almost certainly going to be near the bulb which the OP was working on.
If B is correct, the OP can pull the connector from the switch and short the two pins together. If the light comes on then the switch itself is defective. If the light doesn't come on, then there is a break in the wiring which is almost certainly going to be near the bulb which the OP was working on.
Correct, the latch has a switch inside that completes the ground circuit. 12V is always present at the lamp. I should've thought to tell him to short the two connector pins at the latch to verify the wiring is fine and the latch is at fault. Good catch OP, disconnect the connector at the latch and short the two pins using a small piece of wire or a paper clip. If the light comes on, the issue is with the latch. If not, the issue is with the wiring.