Rear driver window will roll down but not up

Hey all,

I have a 2010 Tacoma and my rear passenger window is having issues.

I can’t roll it up or down with the drivers seat switch, however I can roll the down with its own switch in the back set, but not up. I’m afraid to roll it down and further since it won’t go up.

I’ve checked the fuse, it’s good, and no the child locks aren’t on. All other windows work fine with every switch. Thanks in advance!

 

You could take a test light or meter and and check.
The motor is grounded through the master/driver switch.
So you’ll need to see if the ground circuit is bad in the master or rear switch.

The easiest way would be take a test light and probe the wires at the Rear Door switch. (This ensures it’s also not an integrity problem)
But we’ll keep it simple and assume one of the switches is not making contact.

1. Unplug the rear door switch. (Obviously make sure the master is not on LOCK)
2. Use the meter and set it to continuity or ohm.
3.Then place one of the leads in Pin # 2 and the other in Pin #4. (On the harness side - NOT the switch)
You should read continuity or the meter should change on the ohms scale.
If it doesn’t, it’s almost certain the MASTER switch.


If it does test good, Then you can do a similar test by unplugging the master switch.
I’ll be happy to help there, but I’m betting it’s the master switch.
If not, I’ll step it out later. We’ll keep it simple for now


Rear Passenger Door Switch Connector Pin Out


Below is what each wire should show for the REAR Plug.

Unplugged Rear Switch HARNESS

1. 0v
2. 0v - (Master/Driver switch in UP position 12v)
3. 12v
4. 0v - (Master/Driver switch in DOWN position 12v)
5. 0v

 

Contacts in the switch itself are most likely corroded and need to be cleaned. This is for a 1st gen but the same principle applies for a 2nd gen. I had to do this to my '08 last summer.

https://www.tacomaworld.com/threads/tacoma-window-switch-fix.504215/

 

Here is the pin out for the connector P9 in @caribe makaira chart.

 

@TnShooter is correct, Ground is provided from the master (driver's side front) switch to pins 2 (Green/Black) and 4 (Green) of the rear window switch and power is provided from the D RR P/W fuse 20A in the under dash fuse panel to pin 3 (white).
If either of your grounds are missing you need to check pins 12 (Green/White) and 13 (Green/Red) at the master switch, if they are no good there you have a bad master switch, if they are good you have a broken wire (most likely in the door flex of one of the doors).
If the power and grounds are good at the rear switch you have a bad rear switch.

 

An educated guess would be that the DOWN leg of the Master switch is the likely culprit.
Since the window will roll DOWN using the Rear Switch. But not UP.
That’s certainly not the only thing that could go wrong, but that’s where I’m placing my bet.

Next would be the Up leg of the Rear switch?

But like your signature say , “Test, Don’t guess”

 

So something strange happened…

I took the rear door panel off and located the connector into the switch and began testing with the volt meter. Turned the key on, and stuck my probes in between where the wires terminate into the back of the male connector. I first confirmed that the switch was receiving power, andt confirmed a constant 12V coming to the switch using the diagram @TnShooter posted. I then began probing the “down” and “up” wires to see if a signal was sent. Confirmed the that once I pressed the switch “down” that out 12V was indeed being sent out. Then I pulled the switch “up” and tedted for that signal, it was weak (around 8-9 volts). I continued probing the switch awhile longer, adjusting my leads to make sure my connection was good, then vwah-la! The window began working perfectly again…

I unplugged the connector, messed with where the wires terminate into the connecter, inspected the female port on the switch, and everything seemed in good shape and not corroded. Slowly put everything back together, constantly testing the window along the way and everything’s back on and it seems to be holding up.

Word on the street is that a regulator wouldn’t just go out and revive itself and start working perfectly like that again, so it was advised to me that I likely have a switch that’s going bad. I think based on everything else’s condition, I’d agree. Unless the wires are funky somewhere else along the circuit (maybe in between where the doors open and close) but I think I’m going to grab a new switch and slap it in and see how it holds up. Main priority though is I at least was able to get the window closed before the end of the day. Thanks for the help gang!

 

Good to hear. But I have to give credit where it’s due.
I wasn’t the one that posted the diagram. I just posted the plug diagrams
@Dm93 posted the diagram, kudos to him

​

 

If I read it correctly, you have concluded the UP leg of the Rear switch was “no good”.
If so, my first suspicion was wrong, but 2nd guess was right? (Maybe…..lol)
That’s why Dm93 keeps pounding it in my head test, test, test, don’t guess. Lol

50/50/90 strikes again.