DIAGNOSTIC ITEM 19: Diagnose when the scan tool cannot receive the data sent by A/C-ECU: Diagnosis

Required Special Tools: 

• MB991223: Harness Set
• MB992006: Extra Fine Probe

1. STEP 1. Check joint connector (CAN1) C-105 and A/C-ECU connector C-22 for loose, corroded or damaged terminals, or terminals pushed back in the connector. 
   CAUTION: The strand end of the twisted wire should be within 10 cm (4 inches) from the connector. For details refer to SERVICE PRECAUTIONS  .

   Q: Are joint connector (CAN1) C-105 and A/C-ECU connector C-22 in good condition? 

   YES  : Go to Step 2.

   NO  : Repair the damaged parts.

2. STEP 2. Check the wiring harness between joint connector (CAN1) C-105 and A/C-ECU connector C-22 for open circuit. 
   CAUTION: Strictly observe the specified wiring harness repair procedure. For details refer to SERVICE PRECAUTIONS  .
   1. Disconnect joint connector (CAN1) C-105 and A/C-ECU connector C-22, and check the wiring harness.
   2. Check the wiring harness between joint connector (CAN1) C-105 (terminal 1) and A/C-ECU connector C-22 (terminal 11)

      OK: Continuity exists (2 Ω or less) 

      Fig 1: Checking Wiring Harness Between Joint Connector (CAN1) And A/C-ECU Connector Terminals

      Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
   3. Check the wiring harness between joint connector (CAN1) C-105 (terminal 12) and A/C-ECU connector C-22 (terminal 12)
      Fig 2: Checking Wiring Harness Between Joint Connector (CAN1) And A/C-ECU Connector Terminals

      Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

      OK: Continuity exists (2 Ω or less) 

   Q: Is the wiring harness between joint connector (CAN1) C-105 and A/C-ECU connector C-22 in good condition? 

   YES  : Check the power supply circuit of the A/C-ECU. Refer to DIAGNOSIS .

   NO  : Repair the wiring harness between joint connector (CAN1) C-105 and A/C-ECU connector C-22.