Is the small wire positive battery side ignition wire?

2000 TOYOTA TUNDRA

3,500,000 MILES • 4.7L • V8 • 2WD • AUTOMATIC

RANDYZF

MEMBER
1 POST

Something went very wrong, truck is running very bad. OBD codes showed several different cylinders both banks miss firing, and MAF sensor problem. I pulled battery cables before removing the MAF sensor to clean it. Could not find my can of mass air flow sensor cleaner. So I put everything back together to run to the store. Passive Theft reset and nothing. All electrical works but starter won't turn over. And even worse and what I really need to ask about is the smallest wire (2 cables and 1 wire) that connects to the positive battery terminal is getting hot. There is something seriously wrong because as soon as I connect the battery terminals it starts to heat up you can smell it and pretty warm to the touch.

Mar 13, 2021 at 4:56 PM

JACOBANDNICKOLAS

✓ASE Certified Mechanic
110,194 POSTS

That indicates a dead short. Don't let it like that. It can cause a fire. What color is the wire you are referring to? By chance, is it white? Can you trace it?

If it is white, follow it to the fuse box. Take a look at pic 1. Note that it powers basically everything in the box. Check to make sure the wire itself isn't damaged and then with the battery disconnected, remove the fuse box so you can see under it and inspect the wiring.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-wiring

Let me know what you find.

Joe

Image (Click to enlarge)

Professional Diagram for 2CarPros Members
Click here to log in and view diagram.

Mar 13, 2021 at 10:09 PM

Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.