Remote Keyless Entry Receiver System Check

Check signal voltage waveform between BCM connector M18 terminal 20 and ground using an oscilloscope.

Condition: 

Keyfob buttons released : Refer to  "TERMINALS AND REFERENCE VALUES FOR BCM ".

Keyfob buttons pressed : Refer to  "TERMINALS AND REFERENCE VALUES FOR BCM ".

Fig 1: Checking Signal Voltage Waveform Between BCM Connector M18 Terminal

OK or NG 

OK: Remote keyless entry receiver signal power supply, ground and signal circuits are OK. Replace BCM. Refer to "REMOVAL AND INSTALLATION ".

NG: GO TO 2.

Check signal voltage waveform between BCM connector M18 terminal 19 and ground using an oscilloscope.

19 - Ground : Refer to  "TERMINALS AND REFERENCE VALUES FOR BCM ".

Fig 2: Checking Signal Voltage Waveform Between BCM Connector M18 Terminal 19 And Ground

OK or NG 

OK: GO TO 3.

NG: Replace BCM. Refer to "REMOVAL AND INSTALLATION ".

Check continuity between BCM connector M18 terminal 18 and ground.

18 - Ground : Continuity should exist 

OK or NG 

OK: GO TO 4.

NG: Replace BCM. Refer to "REMOVAL AND INSTALLATION ".

Fig 3: Checking Continuity Between BCM Connector M18 Terminal 18 And Ground

1. Disconnect remote keyless entry receiver and BCM connectors.
2. Check continuity between remote keyless entry receiver connector M120 terminals 1, 2, 4 and BCM connector M18 terminals 18, 19, 20.

   1 - 18 : Continuity should exist 

   2 - 20 : Continuity should exist 

   4 - 19 : Continuity should exist 

3. Check continuity between remote keyless entry receiver terminals 1, 2 and 4 and ground.

   1 - Ground : Continuity should not exist 

   2 - Ground : Continuity should not exist 

   4 - Ground : Continuity should not exist 

   Fig 4: Checking Continuity Between Remote Keyless Entry Receiver Terminals 1, 2 And 4 And Ground

   

OK or NG 

OK: Replace remote keyless entry receiver.

NG: Repair or replace the harness between the remote keyless entry receiver and BCM.