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Test F: Key Operated Switch Circuit (Lock Side)

The key operated switch is built into the door key cylinder. When the key is turned to the lock side, the lock terminal of the switch is grounded, and when the key is turned to the unlock side the unlock terminal is grounded. Furthermore, the key operated switch circuit has terminal +B connected inside the theft deterrent ECU, when nether the lock or unlock terminal of the key operated switch are grounded, battery voltage is applied to the key operated switch circuit of the wireless door lock ECU.

Fig 1: Key Operated Switch Circuit (Lock Side) Diagnostic
G00166978Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Key Operated Switch Circuit (Lock Side) Test
G00166979Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
NOTE: For RKE trouble shooting, see Figure.