Back Door Courtesy Switch Circuit: Description

WARNING: This page is about a different car, the 2008 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.

w/o power back door system:

The back door courtesy switch is built into the back door lock assembly. The switch turns on when the back door is opened and turns off when the door is closed. The body ECU applies voltage to the back door lock assembly via terminal BCTY. Back door open/close state signals are input to the body ECU.

w/ power back door system:

The back door courtesy switch is built into the back door lock assembly. The switch turns on when the back door is opened and turns off when the door is closed. The power back ECU applies voltage to the back door lock assembly via terminal CTYE. Back door open/close state signals are input to the power back door ECU. The back door ECU sends the back door open/close state signals to the body ECU.