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Retrieving Diagnostic Trouble Codes

  1. Locate multiplex control system inspection socket, behind left kick panel. See Figure . Turn ignition off. Connect MPCS Service Connector (07WAZ-001010A) to multiplex control inspection socket for 5 seconds or more.
  2. Turn ignition on. After about 5 seconds, ignition lock light should illuminate and buzzer should sound for 2 seconds and turn off. Self-diagnostic function mode one is accessed after ignition lock light and buzzer have turned off. Go to next step.
  3. If a Diagnostic Trouble Code (DTC) is set, one second after self-diagnostic function mode one is accessed, ignition lock light will blink and buzzer will sound to indicated DTC number. See DIAGNOSTIC TROUBLE CODE INDEX  table. DTC will repeat every 3 seconds. If more then one DTC is present, DTCs will display in ascending order.
    NOTE: Multiplex control unit can fail without setting a DTC.
  4. If ignition lock light does not blink and buzzer does not sound, no DTCs are set. Ensure multiplex control inspection circuit is okay. See MULTIPLEX CONTROL INSPECTION CONNECTOR CIRCUIT  under SYSTEM TESTS. Go to next step.
  5. If no DTCs are set and multiplex control inspection connector circuit is okay, test circuits between switches and their related multiplex control unit. Go to SELF-DIAGNOSTIC MODE 2  under SYSTEM TESTS.
DIAGNOSTIC TROUBLE CODE INDEX

DTC Probable Cause
1 (1) Driver's Multiplex Control Unit Unable To Receive Signals From Door Multiplex Control Unit
2 (1) Driver's Multiplex Control Unit Unable To Receive Signals From Passenger's Multiplex Control Unit
3 (2) Malfunction In Driver's Multiplex Control Unit
4 (1) Signal From Each Control Unit Does Not Match
5 (1) Passenger's Multiplex Control Unit Unable To Receive Signals From Other Multiplex Control Units
6 (1) Door Multiplex Control Unit Unable To Receive Signals From Other Multiplex Control Units
(1) Diagnose using COMMUNICATION LINE TESTS. 
(2) Replace driver's multiplex control unit and recheck DTCs.