When one of the steering wheel audio control switches is pushed, the resistance in steering switch circuit changes depending on which button is pushed.
STEERING SWITCH (SEDAN)
Diagnosis Procedure
WITH BLUETOOTH 1.CHECK HARNESS
Turn ignition switch OFF.
Disconnect Bluetooth control unit connector B126 and spiral cable connector M30.
Check continuity between Bluetooth control unit connector B126 (A) terminals and spiral cable connector M30 (B) terminals.
Check continuity between Bluetooth control unit B126 (A) and ground.
Are the continuity test results as specified?
YES >> GO TO 2
NO >> Repair harness. 2.CHECK HARNESS
Disconnect audio unit connector.
Check continuity between audio unit connector M43 (A) terminals and Bluetooth control unit connector B126 (B) terminals.
Are the continuity test results as specified?
YES >> GO TO 3
NO >> Repair harness. 3.SPIRAL CABLE CHECK
Disconnect spiral cable connector M88.
Check continuity between spiral cable harness connector M30 and M88.