I am having what I assume to be an electrical problem and I would really like to try and solve it on my own. I am very new to working on cars so any and all help is appreciated.
My problem is when I turn on the headlights it blows the fuse that operates my tail lights and dash lights. Brake lights still work fine, just no tail lights and it?s hard to drive when you can?t see how fast your going.
Thanks for your suggestions on where to start.
Take a look around the tail light sockets and bulbs, there may be a short in that area. I have one suggestion for finding shorts that my pop taught me a long time ago:
-get yourself an old sealed beam headlamp from a parts store or off your neighbors car in the middle of the night. Get two lengths of wire w/ alligator clips and clip them to the prongs of the light.
-pull out the fuse that keeps blowing and insert the wires into the fuse contacts. This is very easy with electrical probes or pins soldered onto the end of the wire. Radio Shack should have all of it.
-Now, when you turn on your headlights, the amperage increase due to the short will light the lamp (which is now in place of the fuse), and since the lamp is a good resistor the circuit should be safe from overheating. As long as the short still exists, your test lamp will be on, soaking up all the juice that would normally pop the fuse.
- Now go poking around the area you suspect the short to be. Jiggle the tail light sockets & wires, etc. When you find the short and eliminate it, the lamp will turn off. This is a great way of finding wires that may be cracked or rubbed through and grounding prematurely. Usually just moving them around will Stop it. Once the lamp goes out, you know the general area of the short. What a great project for a weekend, huh?
I've read from another post, that there is a yellow box in trunk, Its the light sensor circuit. I think this a common part that fails, and can repaired or replaced. This may be causing your blowing the fuse. Do a search on the light sensor or yellow box. J
"When a legislature undertakes to proscribe the exercise of a citizen's constitutional rights it acts lawlessly and the citizen can take matters into his own hands and proceed on the basis that such a law is no law at all."
- Justice William O. Douglas
What a great tip! Thanks. I am going to run to the store later today and try this one. To bad it's about 18 degrees here for my fun weekend project. I did try checking all the bulbs and wires and not the red warning light for tail lights is displayed on my dash. So I guess I call that progress.
I can't seem to find the yellow box. I did find a gray box that houses the tail lights on the trunk and as I said before I now have that warning light on my dash. I will see what else I do. Thanks.
Qslim, your dad is a smart man! That procedure can't be lauded enough. I have a 6054 sealed beam with a 2way switch to alter current draw on my workbench, and the other mechanics have to ask me what it does. Hmmm. You ever seen that monolith scene from 2001 - A Space Odyssey?
Whorsen, the cheapest and most likely cause of the short is going to be a taillight bulb. They are 1157s that also serve brakelight duty. If the lead terminals on the base of the bulb squish/melt together, you will short one active circuit through the other inactice circuit all the way to a ground source. Look at those 4 bulbs first to save headache. Check their sockets too to make sure the spring loaded terminals are not melted, burned, etc. A replacement bulb harnass is pretty cheap from Toyota.
The light failure module may be fried in additon, but in most cases it fails due to excessive current. It is in the left side, upper trunk compartment area on the backside of a metal reinforcement panel. It should be yellow plastic with aprox 10 wire white rectangular connentor. Remove the box, use a pocket screwdriver and pry off the cover and pull out the small circuit board. Look for a large burned area. If the burn is around what appears to be a simple buss bar, then you can jump that bar with a soldered 14 gauge wire. If not, try a junkyard or get a new one for aprox $160.
I can't thank everyone enough. As I tested all the bulbs and messed with them I learned that they worked just fine. Then I closed the trunk and it blew the fuse again. I was able to trace the problem to two wires that had been cut but where still under the rubber protective cover so I couldn?t see them. I found them as I was looking for the yellow box, hehe. Thanks again to everyone and all your great ideas.
Vicky
Let this thread be an example to all others. Through thoughtful exchange of ideas resolution arose from conflict. And it actually had to do with a Toyota! Imagine that happening on this board... There is a lesson somewhere, but 'Desperate Houswives' is about to start...
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