Are your Windows, Locks, Keyless Entry, Radios Not Working? Check Engine Light? 4Lo Flashing? (1 Viewer)

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Joined
Mar 16, 2023
Threads
6
Messages
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Location
Los Angeles, California
Symptom List:

-Windows randomly going down on their own
-Window controls not working
-No radio volume, volume changes not shown on screen
-Locks not working
-Keyless entry not working
-Check engine light
-Exclamation point light
-4Lo light flashing like a mad-man
-Trac Off light
-Other dash error lights
-VSC fault
-Other faults

If you are experiencing some, or in my case ALL of these issues, then I have one question for you:
Did you wash your car?

The fault lies in the ridiculously poor choice from the otherwise perfect Toyota engineering department.
Water has ingressed into the connectors in the passenger side wiring harness, where most of the accessories are routed through. I washed my vehicle yesterday, and did not start seeing problems until this afternoon. See trauma attached below.

Note: Water can enter due to clogged sunroof drains, bad sealing on cabin air inlets at base of windshield, bad windshield seal, etc.

If you have these issues, your immediate fix for the symptoms is the following:

1. Remove the Kick Panel on the Passenger Side. If you open your front passenger door (North America), this panel is to the side of your right foot.

2. Disconnect All of the harnesses that are attached in this area. They are all grouped in one location. This includes the two lower connectors (blue one and white one) that are attached with a single bolt, these will be your worst offenders. Attached is a picture of the blue one on the bottom. Note the corrosion one day after washing the LX.

3. Steal your wife's hair dryer (or use your own, who am I to judge). Set it on low heat and high fan so you don't melt the connectors. Blow each of the unplugged harness ports for 1-2 minutes a piece to remove all moisture. Then blow the back of each of the harnesses for a minute as well before you plug them back in.

4. Plug Harnesses in following the color coding of the harness.

5. Start your vehicle, and see if your handy work has paid off. If you dried the harnesses completely, your windows/locks/keyless entry/radio should work.

6. Clear your check engine lights by using the VCX Nano or cable with Toyota Techstream, or use a bluetooth OBD 2 connector and the Torque App.

7. Have a Dark Beer & buy some bitcoin, because God-Damn-It you are the man (or woman).

Note: After doing research, and responses to this post, using a little dielectric grease on the connection can assist in insulating the connector from electrical arcing. I typically use dielectric grease on the connectors that are sealed at the backend, but have not used it directly on small electrical connections. Applying it sparingly on the face of the female connector should assist with preventing this in the future. Dielectric grease is an insulator, but the electrical connections at these junctions should have a tight enough fit to not allow errant grease to disallow electrical signal to pass.

Note: Some might advise using Dielectric Grease. I love this stuff, but looking at the connectors, you'll notice that they are in no way designed to repel water. If you grease the inside, then water can potentially get in the back. Dielectric grease is an insulator, so this has the potential to cause connection issues on pins that are not a tight fit. I might be too cautious on this one, feel free to argue against my position.


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Good write up. But I’m here for the dark beer and the btc 😁
 
A few things missing on your "Fix"
Most importantly, might want to fix the leak, but that's my opinion.
Also more connectors on the opposite side of the vehicle.
Might add seat heaters acting up on your symptom list, brake lights staying on, battery drain.
Here is a good YouTube channel to check out

check out the water leak playlist and sunroof video
 
Corrosion like that probably didn’t happen 24 hours after a car wash; I suspect something has been leaking for a while. Check the sunroof drains and windshield. It does no good to clean up the connections if you don’t fix the leak.
 
Corrosion like that probably didn’t happen 24 hours after a car wash; I suspect something has been leaking for a while. Check the sunroof drains and windshield. It does no good to clean up the connections if you don’t fix the leak.
Absolutely, this has probably happened numerous times already to this vehicle.
 
).

Note: Some might advise using Dielectric Grease. I love this stuff, but looking at the connectors, you'll notice that they are in no way designed to repel water. If you grease the inside, then water can potentially get in the back. Dielectric grease is an insulator, so this has the potential to cause connection issues on pins that are not a tight fit. I might be too cautious on this one, feel free to argue against my position.
This isn’t meant to argue but one of the reasons that I promote the application of the grease is because I believe that the “green” on the junction blocks causes shorts and if the grease is on the block the water isn’t. Ergo, no water, no ”green”, no shorts. And, of course, water will bead on the grease and not spread which removes pathways for shorts.
 
This isn’t meant to argue but one of the reasons that I promote the application of the grease is because I believe that the “green” on the junction blocks causes shorts and if the grease is on the block the water isn’t. Ergo, no water, no ”green”, no shorts. And, of course, water will bead on the grease and not spread which removes pathways for shorts.a
Absolutely agree.
If the connection is tight between the pins and the receivers due to metal on metal, the electrical signal is not impeded. This will potentially seal up the pins from arcing.

Have you or anyone else put a good helping of dielectric grease on the interior of these? No issues?
As you can tell, I'm looking for someone to have Guinea Pigged it already.
 
Absolutely agree.
If the connection is tight between the pins and the receivers due to metal on metal, the electrical signal is not impeded. This will potentially seal up the pins from arcing.

Have you or anyone else put a good helping of dielectric grease on the interior of these? No issues?
As you can tell, I'm looking for someone to have Guinea Pigged it already.
For sure, use the grease. I have for years, as have many others on here. You don’t need a “good helping”. Just some on both connectors will seal the pins from moisture and stray shorts.

Edit: the grease isn’t enough, you have to fix the leak.
 
Also if all of your dashboard fault lights come on, if your windows go up and down on their own, the car turns right when you turn the steering wheel left, and drives up into the sky instead of forward, your gas cap may be slightly loose.
 
It's fascinating how different cars can be. I was with my 200 already up to the steering wheel full of water and still never had because of even a single electrical problem.
But it may also be that sand, dirt and mud have isolated the plugs for years in the best way....

But good to know
 

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