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04' Taco 2wd. Fuses issue ( cig lighter, other aux and door sensor )

826 Views 6 Replies 2 Participants Last post by  Enola Gaia
Hey guys,

I went all over google, my owner's manual, and this forum looking for the answer.

Usually if I open my door my headlights will turn off, if there were on prior to exiting the vehicle. I also noticed that none of my cigerette 12v adapters work in the truck either.

I have all manual locks, and windows.

Does anyone know where this fuse is at? I'd like to replace it soon as my truck doesnt know when the door is open, so my alarm doesnt know it is open either :(.

Please let me know! Thanks guys!
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(1) There's no single fuse common to all the things you list.

(2) Are you saying that *both* the cigarette lighter *and* the 12V power outlet(s) are dead?

(3) Set your dome light to the 'Door' position and see if it comes on when you open the doors. If it fails to open with either door, report back on which one(s) fail to trigger the light.
One more thing - Is your clock working?
One more thing - Is your clock working?
Clock is working.

I set my dome to door, dome light works in any other fashion besides the door.

Im actually not 100% positive on the AUX's, I know for a fact the cigerette lighter stopped working. It was took dark for me to get one of my old working AUX adapters to really test those out.
The dome light not working in the 'Door' position and the lights failing to turn off could be explained by a bad driver-side courtesy switch (or a fault in its wiring).
The 15A Dome fuse is involved in powering the Body ECU - which is the controller for the light auto off function. However, if this fuse were bad you wouldn't have any dome light at all, and the clock wouldn't be lit up. So it's not this fuse ...
OK ... The only 2 problems that have been confirmed are a dead cigarette lighter and a dead light auto-turnoff function. Let's proceed as if those are the only 2 issues, and as if the dual failure has a common cause ...

These 2 circuits do not share a power source or a controller / switch. They do, however, share the same grounding points. Both circuits ground to 2 ground points - IE and IG, located at or near the left and right ends of the reinforcement (structural thingie up under the dash). Both circuits connect to these ground points via single connections through Junction Block No. 3 (of which there are two - no, I have no idea why two things have the same name). The J/B 3 involved here is the one located somewhere behind the dash in the vicinity of the steering column and the cluster.

If either (a) the J/B 3 connections for these two circuits to ground are faulty or (b) the wiring leading from J/B 3 onward to the ground points is faulty, this would explain why these two particular circuits are dead.

Here (attached) are the 2004 wiring diagrams for the two circuits, plus an illustration of the J/B 3 location.


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