Yo
Here is a simple diagram to add an UP function to the factory remote control, on your gen 3 4Runner, to close the back door window from the remote itself.

It a timer module installed near the back door ECU on the hatch, behind the panel.

You can close the back door window using the LOCK button on the remote.
The timer module uses the back door LOCK signal to close the NO circuit relay on the board for a predefined time set by the little knob and bridge also on the PCB.

In my case, the back window closes in about 6 seconds using the key. I set the timer module for about 10. Depends on how charged your battery is... and how well maintained your BACK DOOR is.

A separate relay is used to disable the timer module when the ignition key is in the ON position. This prevents the timer module from operating, so the window doesn't close if you are just locking your doors while driving. The relay used is the same as on the module itself. Check pic on diagram.

Everything in the red box is what's added to the main electrical diagram of the POWER WINDOW (REAR). The door locking motor in this diagram is from the WIRELESS DOOR LOCK CONTROL diagram, but the wires are right near the back door ECU, so no need to remove the metal panel.

The installation is done by just removing the back door plastic panel. The wire colors are for 01 4Runner and should be easily identifiable near the ECU.

The current consumption of the module is negligent and should not drain your battery as it is much less than a factory alarm.

Consider safety first when closing the back window, as Toyota did not intended it to be this way in the first place.

You dont want a cat or a dog or god forbid a kid get caught up when you remotely lock the car and the window closes without you making sure it's clear to do so.

You can ask the mother in laws to assist when remotely closing the window.

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