Weird Electrical Issues after car wash

Hey everyone,

I appreciate the help in advance.

Last night I took the truck to the car wash and halfway through while the water was spraying on the tailgate the interior dome lights turned on. I turned the car off and on again and they continued to stay on while driving. You could interrupt the power by turning the switch to off but door open they stay on forever.

So that's just the beginning I'm going to cut to the chase here in order of issues discovered:

Dome lights stay on: (Semi Resolved its self)
Troubleshooting Ive done so far:
Disconnected the battery for an hour
I pulled the fuse for interior lights and its fine.
When the dome light switch is set to off the lights will turn off.
when the dome light switch is set to doors the lights stay on. But they are dim
On is on.
Dash does not indicate doors are open so its not door sensors.
Looked at all harnesses in the engine compartment, and under the truck to see of there is visible water.
What I think:
There is a short somewhere allowing the lights to bypass the doors closed indicator.
At this time:
Issue has resolved it's self for now. But I still want to know what caused it. I imagine water in a harness.


Driver Door: (Semi Resolved its self)
So issue number 2. The driver door controls half work. I can roll down the driver window but the other three windows do not function from this door and the locking button does not work.
Troubleshooting Ive done so far:
Pulled the fuses and checked them
All windows function from there dedicated door switch
locks work from passenger side door and key
Mirrors still work
What I think:
There is a short somewhere causing the door panel to not fully function.
At this time:
Issue has resolved it's self for now. But I still want to know what caused it. I imagine water in a harness.


Dash Lights:
This morning after the other issues had resolved themselves I started the truck and the, traction control light, ABS, and stability control dash lights were all illuminated and the Locking rear diff light is flashing.
Troubleshooting Ive done so far:
Turned the truck off and back on multiple times
Cry
Go to Toyota to make an appointment because I have to go to work
What I think:
Same, water has to be in a harness or fried something.
At this time:
Waiting to see if more time causes the car to dry out completely and issues self resolve like above.


If anyone has ideas of which harnesses or fuses I should check please let me know. If anyone has a suggestion other than push it into the ocean and call insurance I'm all ears.

Thanks for any help.

Nick

PS: A weird thing the truck has always done. I got it new in 2019 and Toyota put an alarm in it for me. Free of charge. Well that alarm has sometimes just gone off when you unlock the car and start it. There is no way to stop it, turn the car off, on, put it in park, drive, etc. You just have to wait 30 seconds and look like an idiot.

Additional PS: Tail light is broken. Large piece of plastic is missing.

 

So two things, which if you had mentioned separately (like car acts weird, I have an aftermarket alarm) and (car acts weird after getting wet) both can cause electrical issues. If you want to take a methodical approach to this, my first course of action would be to see if its water-related. Sunroofs and the third brake light have been known to cause trouble. Checking for moisture around the center console upper controls would be the highest priority. You have lightning and door lock stuff up there as well.

Next I would try to figure out what all was installed in your car and look for the main brain box. If its aftermarket it may have required wire cutting and splicing, or wiretaps. Inspecting those connections or completely removing that hardware may be required to rule that out.

 

Sunroof?

 

If that's true about the brake light I should add. I have a cracked and super glued tail light. I also believe the issue started while the car wash was at the back of the vehicle. Are the issues you are aware of from the tail lights similar to what I am having?

I am going to trace the alarm this evening and see if there is anything not properly sealed.


Sunroof: I'll double check the sunroof for leaks but the sunroof motor and switch do still work at this time.

 

Was it a touchless car wash with a undercarriage sprayer? If so the higher pressure water is a big issue. There are so many small gauge wires and connectors under the truck for high pressure sprayers to f up. And some people even had their rear fender sides pushed in by them.

Many Tacomas can’t even survive water crossings very well. If your 4wd actuator also gets stuck, you know why.

 

Yes it was a high pressure touch less car wash. Didn’t realize it when I bought the wash at the pump.

 

Hope it all gets sorted out for you. That’s really poor luck. Luckily I avoided car wash issues ever since I put in a RTT and Prinsu rack, otherwise I’d probably have written the same type of post as you did.

 

I would go under the truck and check the integrity of every single wire and connector you can find, hopefully it’s something as simple as that.

 

So after parking the truck in the sun for a few hours and coming back to it after a meeting I started it and none of the issues persisted.

Next steps, is to do and suggested check all harnesses and wiring for damage. Fix anything if anything. Inspect the after market alarm wiring, and fix this tail light.

 

I think its just the sunroof leaking on the overhead light. Thatd be my guess. This forum is rampant with leaking sunroofs. Probably not designed for overhead pressure washing.

Ive climbed and pulled wires a bunch under my truck. There are not a ton of connections down there. And they are all wrapped well. Not likely the problem.

 

That’s a good point, I’ll actually start there and see if I can find anything. Because all of the buttons for traction control etc are located in front of the sunroof.
Thank you

 

Based on this and your most recent comment, I'd definitely venture to say your third brake light is the issue (assuming what you meant by cracked and super glued tail light).

All sunroofs leak. They are designed knowing this and they have drains and tracks built into the truck to account for this. It wouldn't hurt to check to make sure they're not clogged (should be one in each corner of the sunroof housing area), however them being clogged and backing up is unlikely, especially if you're not seeing any water dripping on you.

 

[QUOTE="They are designed knowing this and they have drains and tracks built into the truck to account for this. It wouldn't hurt to check to make sure they're not clogged (should be one in each corner of the sunroof housing area), however them being clogged and backing up is unlikely, especially if you're not seeing any water dripping on you.[/QUOTE]

In theory. You must be an engineer if you think the design always works in practice.

 

All sunroofs leak to a degree. The sunroof is designed with this in mind. The water harmlessly moves to one of the 4 corners of the sunroof area and drains out through one of the 4 built-in drains. These being clogged would be the only thing that would cause any issues and not only is it unlikely, you're also likely to see other symptoms.

 

I can't say I've inspected all trucks, but I've certainly inspected my own and done quite a bit of looking into it after hearing about it. The design works quite well.

 

do you have ANY AFTERMARKET, wiring, lights, leds? all known issues. Ski

 

I wouldn't recommend any car wash. It's all recycled water. Then again I'm not one to ever wash my truck. We have good windy rain storms that do a good job.

 

defiantly fix that brake light