Please help strange electrical problem

Tacoma has been acting strange lately, 2018 trd sport, when I turn the truck off it goes completely dark, no interior lights will function , except the windows will work, and even with the door open? The gauges are all stuck at idle speed and the temp gauge is pegged in the middle also the fuel gauge does not move ? Checked a bunch of fuses but lost as to what it could be. Anyone have any ideas or suggestions?

 

Scan for codes and see what comes up.

If everything else works when the vehicles running then i'd guess a wiring or network issue.... this will be a hard one to give you help with over the internet without someone being there to start testing things.

 

Yes I'm aware it could be a difficult one to diagnose. There aren't any codes showing unfortunately. Probably rodent damage im guessing but where would this problem originate from so I can start looking. What do you mean by network issue ?

 

If it just happened out of the blue I’d start visually looking everywhere you can for anything loose or chewed. Other than that, the dome lights is a pretty convenient tell. If you can find someone with an electrical manual for the truck you can follow that circuit and probably find the source of all the problems.


Another thing, which seems less likely, is a loose ground wire. Has any work been done to the truck recently?

 

Guess I forgot to mention, when you he truck is running, all the dome lights function perfectly. Power locks function. Just when u push the button it shuts everything off immediately and it won't function until it's keyed on again?

 

I'll poke around on some wiring diagrams here in a bit when I get a chance.

So everything works correctly when the engine is running and with the switch in the run position?

Do you have the keyed ignition or push button ignition?

A list of everything affected may help too.

 

Push button ignition.

when it's running I have basically full function as far as I can tell. As soon as the push button ignition is keyed off, the truck goes dark no

headlights, interior lights, radio, no key fob function for power locks, no hard switch function, but the windows will work even with the doors being opened. Checked a pile of fuses under the dash and hood everything looked good.

 

Gotcha, I'll poke around in some diagrams when I get a chance and see if I can come up with at least a place to start.

There's no aftermarket electrical modifications such as alarm/remote start, wiring, add a fuse, radio, etc correct?

 

Remote start only. Was thinking this would be a great place to start just unhooking it completely. It's all electrical taped together. Just looks awful.

 

I think I'd start with the ECU-B No3 fuse (10A) in the underhood fuse box.
Also make sure the short pin is installed correctly.

Yea I'm not a fan of them, they can cause a host of issues when they fail and most are poorly installed.

 

Different module/ computers talk to each other for various reasons. Example is abs/traction control module will talk to the ecm to reduce power when you're sliding. Thats networking.

A wiring diagram being sent you will be the most helpful

 

Just re checked those fuses and they all loook to be making a solid connection.

 

Video

won't let me post sorry .

 

You have to upload your video elsewhere and link to it. Tacoma World doesn't allow direct uploads of videos.

 

Any chance it could be the actual start stop switch ? Is that a dash out job ? Noticed when in the truck with no key it doesn't recognize when u press start an say no key or do anything really?

 

Srry for not getting back to you last night, TW kinda went nut's with people with electrical issues and I lost track of who I had replied to.

Might swap that fuse just to be sure and check it for power on both sides, if power is good at that fuse we're gona have to go to the Body ECU and check some things as everything you mentioned that isn't working properly is tied to the Body ECU.

What were the event's that led up to this issue happening?

I don't think so, that would only affect the vehicle keying up it shouldn't affect the lights.

 

Sounds really weird any more details or backstory?


Original owner?

Harsh climate??


Did it always work correctly?


How soon after the remote start install did it start having issues….and who installed it ?

Any other recent service/accident prior to it acting up?