Weird issue new battery no power after mhg rebuild

[87silverbullitt]

Hey guys, so after completing my rebuild with a mhg and arp studs and fixing/cleaning up miscellaneous things, I went to start my car with my old battery that had been sitting for almost a year. Sure enough battery was toast, I was able to get some power when I hooked up a booster but that soon died. This was yesterday. I hooked up the battery from my daily driver that I knew had power, and I noticed that when I opened my door it was ad if there was no power since my door light didn't come on, but right as I sat in the car it came on? Then today, I went out and bought a new battery for the supra, and right away my car has power and it starts up. I let the car warm up, took it literally 1 min around the block for a little spin, come back and shut the car off. As soon as I shut the car off my car had no power again so I try cleaning up the terminals and still nothing :s I can't figure out what it could be cause there's no way the battery is dead already, and I checked the wires on my alternator and everything seems fine. Some help would be appreciated!!

 

[hvyman]

Check the little blue wire at the battery. It can look connected but really not be.

 

[87silverbullitt]

Check the little blue wire at the battery. It can look connected but really not be.

Are you talking about the two blue wires with the little white connector poking out from underneath the fuse box? I didn't have anything connected to that before either.

 

[planemos]

Remove both battery terminals and reconnect them. That happend to me once. I had it connected. It looked fine but had no power to anything. I took off both terminals completely, put them back on tight and bingo power. Give that a shot if you havent yet. Also make sure all wires are not touching hot parts like the EGR.

 

[tyang82]

Try replacing the terminals. It doesn't cost much and worth a try.

 

[3p141592654]

...or you could use a voltmeter and actually do some troubleshooting... nahh, replace everything.

 

[Crypton2006]

...or you could use a voltmeter and actually do some troubleshooting... nahh, replace everything.

Right!

Sent from my SCH-M828C using Tapatalk 2

 

[87silverbullitt]

Remove both battery terminals and reconnect them. That happend to me once.

.

I wrote in my original post that I did take the terminals off and try cleaning up the batter posts but ya I'll just buy two new terminals for it. I remember my ground side terminal looked pretty finished, some plastic peeling off the bottom but I thought it was still getting a good connection. Would the bad ground off the battery do it? Or a specific fuse I could have blown? I checked all the basic ones but they all looked fine from what I could see.

 

[87silverbullitt]

So I ended up buying two new battery terminals and still nothing, I ordered a new main relay that sits in the top right corner of the fuse box in the engine bay, maybe that'll do it, I think it's time for me to invest in a voltmeter..

 

[87silverbullitt]

I replaced the Main relay in the fuse box and still nothing. Any ideas anybody? I have zero electrical power. Would the ecu be culprit?

 

[hvyman]

Check the little wire at the battery terminal. Not the big one that goes to the starter. The little one usually blue or white.

On the positive side.

 

[Crypton2006]

The ECU dose not control any of the chassis power. You really need to go to Walmart and buy a 8 dollar meter. One that measures Voltage and resistance.
After you have done that check for voltage across the battery. If you have >11 volts then try checking from the positive terminal of the battery to the body or motor, just something bare metal. Lets start there let us know what you come up with.