Tundra won't start

Picked up a new to me 19 tundra 5.7l about 2 months ago. Had about 2 weeks and it wouldn't start. (Dead battery) took it to schwabs and got a new one. Today the same issue, schwabs replaced the battery. So now I'm thinking alternator. Dug out the meter and with it running it reads 13.5volts. Isn't this within reason or should it be higher? I'm stumped

 

Check the fuse first - https://www.tundras.com/threads/alternator-troubleshooting-2018-tundra-1794-crew-max-5-7l.125613/

I realize your battery is new but also clean/check for corrosion around your battery terminals.

 

Check your battery voltage

 

Might have bad main fuse, bad ground, or bad cables all around. The whole system has got to be good, a good battery and good alternator is only part of the system. Good luck!

 

Welcome to the forum from OKC!

 

You don't have an AGM battery so don't pay any mind about updating fuses. You just need to verify yours isnt blown. The thread below is a decent read for troubleshooting an alternator. OP figures it out in post #14.

https://www.tundras.com/threads/charging-alternator-problems.97131/

 

Not super mechanically inclined but the fuse looked fine, terminals in good shape. Looks like it has a parasitic draw. Pulled the negative cable and tested it with the meter. Was hovering at 1amp to 90mil amps. Is that the culprit for dead batterys? The previous owner had installed after market stereo,Amp, subs. Running board lights, 6 different light bars.. viper alarm. Going to assume one of these is the issue.

 

Yeah, I'd start by disconnecting one at a time and measuring to isolate the culprit.

 

Well if you have power, then something to think about. Possibly the fuel pump. If so make sure the system gets flashed.

https://www.youtube.com/watch?v=Xc7fPGVFq9I

 

That Viper alarm is probably the culprit. Does it have a remote start?

 

It does yeah

 

Are there any additional wires added to your battery terminals? If the main power to the amp or subs was connected directly to the positive terminal, my guess is your problem lies there. You mentioned 90 ma to 1 amp? 90 isn't too bad but 1,000ma is a real problem.

 

It was only about 90 to 100ma. It took roughly a month to kill the last battery. There's several other wires hooked up to the positive terminal. I went thru and disconnected everything 'extra' that was on the battery. Still had a draw...the only way I got it to stop. Theres a heavier gage wire hooked up to the battery that goes to the fuse box I believe to power it. So I pulled fuses for radio, alternator etc..no luck. It's a bit beyond my capabilities of figuring out.

 

A month of the truck not running? That might be a bit long with all the normal parasitic drain these vehicles normally have.

 

I had bought a battery when I first bought the truck. Went to start one morning and it was dead. Took to our tire store and got another one. Assumed that fixed the issue. Last week..same thing..dead truck and battery. About month since I had purchased battery before it killed it. I thought at first it'd be the alternator. At this point I wish it was..lol trying to narrow down a parasitic draw is a pain in the butt