Second Gen Tacoma Short Circuit

Hi all! Im new to the community, and I have been having several electrical issues with my Tacoma. I have a 2007 Tacoma that I owned and was my daily driver for about 3 months. I decided to work on the truck, I put a lift on, suspension, new interior. I haven't touched the truck much and its been about 3 months.

I got around to completing the truck and I was wiring some retro fit headlights. Everything was working fine and I let the truck idle for about 15-20 minutes, turned it off. A few days later I went to body work the truck and I was getting ready to roll it into the garage for paint when I turned the key and the truck sputtered, I turned it again and the truck turned on. I reversed it into the garage and it was on for less than 2 minutes and I started to smell smoke and I shut the truck off. I opened the hood and around the starter was smoking. I went to try to start the truck again and the start only clicked and all the lights turned on inside the truck. To me it was obviously a starter issue so I had it tested, was no good at all, so I replaced the starter. I went to start the truck, didn't even crank. I then got the battery load tested, my 6 month old battery only measured at 6.2 volts. I went to start the truck with a new battery, I connected the power then the negative and the negative terminal sparked. I instantly started seeing a slight bit of smoke from the power terminal, I disconnected it and power terminal was super hot. I've checked every fuse and they are all fine, new battery and starter, but I am still having the same issue.

I should also mention that I wanted to avoid causing any electrical issues and I bought two of these wiring harnesses, one for my light bar and one for halos, the only wires on the truck that I touched were the turn signal wires which it tapped into with T-taps.

Any advice would be very helpful, Thank you.

$13 Nilight 10011W 16AWG Wiring Harness Kit-2 Leads LED Light Bar 12V On/Off 5 Pin Rocker Switch Power Relay Blade Fuse for Jeep Boat Trucks, 2 Years Warranty

https://www.amazon.com/Nilight-NI-W...+light+bar+harness&qid=1637370851&sr=8-3&th=1

 

Out of curiosity, did you get a battery that had the polarity of the terminals reversed? Essentially making you hook up the positive to negative and the negative to positive?

It's a stupid question, but I've seen it happen before, given what you stated, it's a very real possibility.

 

No, I actually took the battery out before the starter went bad and when putting it back in, it also sparked the same way. Both batteries are duralast standards.

 

Take take the cables off.
Test each battery cable for a short.

I would start with the battery + cable.

 

Have you disconnected your alternator and checked if the short is still there?

 

How would I remove the battery cables to test them. That should be done with a multimeter right? I can’t even connect the battery without it smoking.

 

I haven’t disconnected the alternator, so far the only adjustments I made was a new starter and battery. I think that would be next but I’m not sure if the alternator could be causing the issue.

 

It's possible it's shorted, it doesn't happen often but I have seen them short out.
Battery cables shouldn't be hard to check, follow the red cable down to the starter and look for spots where it may have gotten pinched, rubbed, or melted.
Otherwise my method to find a dead short like that would be to put a high amp headlight bulb in line between a battery cable and the battery and start wiggling and/or unhooking things until the bulb dims or goes out.

 

I’ll have to look into it, I’ll definitely get to it tomorrow and give an update.