Inspection Procedure

INSPECT TELEPHONE SWITCH ASSY (MAYDAY SWITCH)
1. Disconnect the O2 telephone switch connector.
2. Check that the continuity exists between the terminals of the switch when each switch is pressed.
  Standard:
  
  Fig 1: Terminals Specification
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 2: Identifying Telephone Switch Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. NG: REPLACE TELEPHONE SWITCH ASSY
2. OK: GO TO NEXT STEP.
CHECK WIRE HARNESS (TELEPHONE ECU ASSY (MAYDAY ECU) <=> TELEPHONE SWITCH ASSY (MAYDAY SWITCH)) (See ELECTRONIC CIRCUIT INSPECTION PROCEDURE )
1. NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
2. OK: GO TO NEXT STEP.
  REPLACE TELEPHONE ECU ASSY (MAYDAY ECU)
HINT:

If this DTC is not cleared even when the mayday ECU is replaced, replace the mayday assy (transceiver, portable phone-L battery (back up battery), bus buffer ECU and mayday ECU).