Help! Serious Electrical Problems!, The weirdest thing I've ever seen... Options

[Coomer]

I'm so confused and scared right now...I can't figure out for the life of me what's going on with my car.

It started with me trying to start it, and only the fans turning on. I checked the fuses and none were blown, so I checked the switched wire at the starter, and it was giving me no voltage.

I then unplugged the battery and went inside to take a break. When I came back out and plugged the battery back in, I noticed that the trunk light didn't turn on. I looked at the dash and the door open light wasn't on either. I tried turning on the parking lights and they didn't turn on. I tried the horn and it didn't work. Basically, nothing on the car works.

This is where it gets confusing. I've got a fuse 6" from the battery, and it's in good shape. Figuring I'd popped some other fuse, I checked all of them in the dash and under the hood, and they were all good.

I pulled the main 50 amp fuse under the hood and tested voltage on the hot side. Voltage started at around 10 volts and over a couple seconds rose to 12.4 volts and held there.

I then tried the same thing for the horn fuse under the hood, and it started at about 8 volts before rising to 12.4 and staying there.

At this point I disconnected the negative cable and came inside. Someone suggested testing voltage between the terminals and the clamps with the headlights on to test for a bad battery connection, but this yielded no voltage. At the battery terminals, I'm getting 12.4 volts. At the battery's fuse and a bolt in my trunk, I'm also getting 12.4 volts.

At this point, I'm so confused. I've never seen anything this weird in my life. Anyone have any ideas?

[Coomer]

Finally, I made some good progress tonight. I fixed all of my interior/non-engine problems. A picture is below, with an explanation at the bottom.



Basically, I guess I must've had something in that slot before. I guess it fell out or whatever...initially I figured that slot was useless(although one side was giving +12 volts), since it has a box with a slash through it on the fuse layout printed on the fuse cover.

However, that's not the case. When I pulled apart the fuse box and looked underneath, I realized that the three fuses to the left of it(20 amp radio fuse, 15 amp ECU-B fuse, and the 10 amp dome light fuse) get their constant power from the side of the empty slot that wasn't getting +12 volts. So I popped in the little connector that fits in there from the purple Celica, and now everything on the interior works again.

Lots of stuff revolves around the integration relay inside the car near the interior fuse box, and if the dome light fuse is blown or isn't getting power to the constant side then it messes with all kinds of stuff not even related to the dome light, such as the lights not being able to be on unless the ignition is on.

Now my stereo, clock, dome light, trunk light, door open indicators, seat belt light, and lights all work correctly.

What's very interesting is that there's NO mention at all in Toyota's BGB and electrical diagrams about this jumper piece of metal...I only found out what it did by pulling the fuse box apart. I wish there would've been...it would've saved me a ton of trouble.

That's the good news. Now for the bad.

I'm still having engine problems. The car still won't start.

So I tested the grounds on the block, head, tranny, and intake manifold, and they all are solidly grounded with the ignition off. However, with the ignition on, the engine/tranny give me a ground that yields +9 volts. If I move the ground probe of my multimeter to a good chassis ground(even the ground wires right where they bolt to the engine/tranny), I get +12 volts.

Also, if I place the ground probe at a solid chassis ground and then place the positive probe on the block, head, intake manifold, or tranny, I get +3 volts.

I'm thinking that I've got some sort of a +12 volt wire shorting out somewhere on the engine. Does that sound like something that would cause this?

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