[Kyle1!]

Our kind sheriff let me know the other night that I had no taillights. If there is one thing I hate it is electrical wiring troubleshooting. I have the shop manual so that is a big plus. Here is what I know. The tail fuse is OK until I turn on the headlight switch then it blows. I have checked continuity in the headlight switch and tail light relay which were OK. Wiring in the trunk looked ok from a quick scan. Any ideas?

Brian

 

[71Corolla]

Pull the negative on the battery, and with a test meter grounded on one terminal, you'll have to check each wire in the taillight section. Keep in mind that some of the wires are actually ground of course (your manual will be a big help here).

The most common shorts are wire chaffing, the insulation is damaged and the wire touches a metal part of the car, or the wires over heats somewhere and the insulation gets damaged, causing side by side wires to make contact.

BTW what car do you have?

 

[atobe]

check for broken wires near the trunk hidges

 

[Kyle1!]

88 3sfe camry

Sorry about that on the car. I will look better in the trunk area. I just did a quick survey of the trunk area (alot of rust, dirt from gravel road and wetness) and didn't see anything obvious. I will have look closer next time. Thanks

Brian

 

[Mike Gerber]

^ What atobe said. Open up that loom of wires in the trunk near the driver's side trunk hinge. Check for broken or frayed wires. Repair what you find.

Mike

 

[hairball]

replace the tail light control box (officially called "Lamp Failure Sensor") in the trunk. It looks like this...

99.999% chance you'll find your problem. If you're not familiar with it, open your trunk, pull the material away from the driver's side and you'll find a yellow box. Unplug it, then with a very small screwdriver, pry it open. The circuit board will fall out. You'll most likely find a burned diode as indicated here...

 

[Kyle1!]

Looked fine

I did a quick pull of the yellow box over lunch and nothing burnt on the board. Looked clean no burn marks. Only thing wrong with the board was some of the green film was peeling off at the bottom from the plug. I could try the one from the 91 and see if that helps. Thanks for the tips

Brian

 

[hairball]

oh, you're very welcome, Brian. Anything to help fellow Camry owners/drivers. That's a GOOD thing that nothing was burned. But odd. These things don't last long at all. I'd be excited to know what you find out. Or if another one works.

 

[Tnexus]

I had a similar problem with my tail lights. My problem was actually one of the solders on the back was bad. If you turn the circuitboard over, look at the solders where the connector is. One of those ended up frying somehow and it stopped my taillights from working. I missed it in a passing inspection twice before I stopped to examine each pin solder. It was just a tiny blemish, but it was enough. I just put a dab of solder back on it, and it's been working fine for months.

 

[hairball]

Here is how to test (in picture format)

Testing the Sensor:

Testing the relays:

Taillight Operation Outline:

 

[bmwm5lover]

This, Had same problem.

replace the tail light control box (officially called "Lamp Failure Sensor") in the trunk. It looks like this...

99.999% chance you'll find your problem. If you're not familiar with it, open your trunk, pull the material away from the driver's side and you'll find a yellow box. Unplug it, then with a very small screwdriver, pry it open. The circuit board will fall out. You'll most likely find a burned diode as indicated here...

 

[PaulPR]

As others have said, check the wiring that flexes when the trunk open/closes. I believe (can't remember for sure) there's a ground wire in that bundle too, so if the insulation has cracked and wires broken, it's possible the ground wire has contacted a hot wire.