Toyota Repair: tail lights not working(continue), phillips screws, jumper wire

Question
Hi Ted,

I did as you advised. The tail relay is a red box, right? The circuit board is ok, no burned spots. I checked the socket again, the tail light spot shows -12v when it is off, but the break light spot shows 0v in the same condition. Is it correct? Could you give me more advice to fix this problem?

Thank you so much!
Kevin.

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Subject   tail lights not working(continue)
Question   Hi Ted,

Thank you for answering me so quickly.
You know, my car is using the 1157 combo bulbs, the break-lights share the ground line with the tail-lights(the break-lights work well), and what I did before was checking the voltage between the bulb sockets and the negative terminal of battery directly. I checked the wiring diagram, it seems having a relay working with the tail lights. I don't know where is the relay located in, and how to test it. Could you please give me more suggestion?

Thanks!

Kevin.

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Subject tail lights not working
Question Hi Ted,

My 93 Camry Wagon's tail lights and parkings lights do not work abruptly in the same time. Break lights, back-up lights, license plate lights and signal lights are all ok. In the beginning, Rear Light Failure Warning Light was on, but it became off from the second day.
I checked the fuse and the bulbs and wire. The fuse and bulbs are ok. When all of the bulbs were removed, the results of all of the sockets were 12v, but when any one of tail bulbs is installed, the other sockets would be 0v.


Thanks!
Kevin
Answer It sounds like a ground problem, make sure you check all the white and black ground wires in the bulb holders, they have phillips screws that attach into the plastic housing and go to a common ground point, if these screws become loose you will lose the ground and the lights won't work,to verify this make a jumper wire directly to ground the lights should work.
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Answer   The relay is located on the left side you will have to remove some panels in the rear cargo area, it's mounted on a metal bracket, once you find it you can open it and look for any burned spots on the circuit board.  

Answer
I'm beginning to think that there may be a problem with the switch on the steering column, remove the covers around the steering column and disconnect the connector from the switch, you said you have a wiring diagram, identify the wires that go back to the taillights, find a power source either from a fuse or any other hot wire, put a jumper wire in to power up the tail light wire and see if they will work when bypassing the switch, if not, there is an open circuit between the connector and the tail lights.