2013 Toyota Tundra 4x4 5.7 Electrical problem

Hello My name is Jim and this is my first post. I found a post on this forum that was very close to the problem that I am having although the solution was determined to be a bad fuse.

I parked my truck and it sat for 2-4 days and had no indication of an electrical problem, it was running fine. I started it up the other day and it was like the battery was low but it did start. I noticed that the volts were low about 10 or 11 volts when running as if it was not charging. I was not able to get the floor shifter out of park I had to depress the bypass button to get it out of park and I noticed other accessories were not working I.E. Power Windows, A/C and heater, Rear Window, Blinkers and possible a few others. I have checked all fuses under the hood and dash and they all appear to test fine. I have looked for any indication of a rodent under the dash, under the hood and under the truck and did not see any indication of a nest or scat. I went ahead and installed a new 150 amp alternator and nothing has changed. Any help would be greatly appreciated. Thank you.

 

Battery good? Cables/connections good? Curious what the battery voltage is? Have a meter?

 

BTW, welcome to the family!

 

Cables are original and in good shape, battery is charged 12.6 volts, yes I have meters
Thanks

 

You may want to look everything over closely, might have a loose ground strap somewhere.

 

Modified anything lately?

 

I would check the 180/140 ALT fuse in the fuse box under the cab.

 

No, nothing has been modified or changed lately

 

How do I check the 140/180 alt fuse aside from taking the box apart?

 

Also, I wanted to mention that I had the old alternator bench tested at the auto parts store and it passed, I went ahead and put the new one on and nothing changed.

 

Might be time to study up the wiring diagrams. Click on the forums button, scroll down to garage heading, scroll to electrical subheading. Click it. The wiring diagrams are listed right there.

 

I also wonder what happens if you use a jumper wire to feed power to one of the dead spots? Will all the other dead spots come to life? Might be helpful way to troubleshoot.

 

Looking into this now. I think your engine fuse box is fine. The 4 Blue 15A fuses you point out with no power are for the headlights. Turning the headlights on should power these fuses. The other 5A fuse with no power is the rear window defogger, turning it on should power this fuse.

Your problem seems to be that half the interior fuse box is dead. Hopefully soon I will have an answer as to why. Looking at wiring diagrams now.

 

I thought about doing the jumper wire test, I didn't know if that was safe or not but still might try this

 

I would look in the window of the 140/180 fuse and see if the copper strip is not burned into.

 

You can throw a 10 amp fuse in the line to be safe and you will know really quick if there is a short in the circuit

 

alternator fuse looks good I believe

 

I need you to verify if you have power on the two fuses I put the red box around here. I think you may be off by one fuse when pointing out which ones have power. Check the 7.5A and 15A fuses in the red boxes. I believe these should be the only two with power on this side.

The one you drew the orange arrow to should not have power, but the one above it should.

 

Whatever you do, when you get it figured out, post it up for the next guy(s) to reference. Thanks!

 

Jeff_5_7 I learned that the 7.5A fuse that I mentioned has power only when the key is on and the other 7.5A and 15A don't have power key on or key off

 

Sorry the two I pointed out in red will only have power when the headlights are on and the tailight relay is closed. If you tested them with the headlights off they will have no power

 

Pull this 7.5A fuse (right below 30A big one) and replace it. Hopefully it is bad. I am 99% sure this is your problem. You saying the one 7.5A fuse on the left side has power still is odd as it shouldn't.

Anyway remove and replace the fuse in the red box and post back if that fixed it. Hopefully so.

 

Jeff_5_7 With the headlights on I have power to the 7.5A and the 15A fuses you circled in red

 

Darn it did not fix the problem, just as a side note when I test the fuses I probe both contact points on the fuse and they have power on both sides

 

Something is not right here.

This is how the system works. The black wire at the top brings in power and is powering all the fuses in the red box. The ones in the black box do not have power however they should. The power for these flows through the ignition switch (via the 7.5 AM1 fuse you just checked). After the ignition switch is on, power from the back side orange and green wires close the relays to power the fuses in the black box.

You are saying you have power on the 7.5A ACC fuse in blue but for that to happen the top relay has to close. If it is closing, all the ones below it should be also meaning all fuses should be powering on.

 

Jeff_5_7 Is it possible that a relay is bad and not closing?

 

Its possible the ignition switch is not passing the power into the relays, this would be an internal failure in the ignition switch which is not very likely. It is also possible you have a bad ground on the other side of the relays that is not letting them close.

Are you good with a multimeter? Some measurements on the wires at the connector coming into the interior fuse box could give some clarity.

Highly highly unlikely all 3 of those relays failed at the same time. They are just not getting the proper signal to tell them how to operate.

 

Jeff_5_7 I am pretty good with a multi-meter.
Are these relays under the hood in the fuse box?

 

I know my diagram shows Pin 45 as orange but on your 2013 its actually beige or brown in color.

Check these wires coming into the fuse box at the connector. With the ignition switch on 12V should be coming in on both to power the relays. A good ground on Pin62 is needed also to close the relays.

While down there also check Pin 47 (White) to make sure 12V is coming out on this wire. This is from the AM1 fuse you just checked and sending power into the ignition switch.

 

@RainMan_PNW can you take a second look at this also and help me make sure I am not missing something. He says the AM1 fuse is good which means he should be getting power into the ignition switch on the white wire.

Why it is not moving through the ignition switch to power the relays and fuses I am not sure. If everything is correct so far I suspect a bad ground for the relays or an internal failure in the ignition switch. Very odd.