AIR SUSPENSION SYSTEM, Diagnostic DTC:C123A12

DTC Code DTC Name
C123A12 Supply Voltage Circuit IG Voltage Malfunction

DESCRIPTION

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Memory
C123A12 Supply Voltage Circuit IG Voltage Malfunction

  • When the suspension control ECU recognizes the power switch condition as on (IG), power switch off signals from the main body ECU (multiplex network body ECU) via CAN communication are received for 10 seconds or more.

  • LUG-IG1 NO.2 fuse

  • Wire harness or connector

  • Suspension control ECU

  • Main body ECU (multiplex network body ECU)

 Does not come on Yes

WIRING DIAGRAM

B004TO9E01

CAUTION / NOTICE / HINT

Note


  • Inspect the fuses for circuits related to this system before performing the followinginspection procedure.

  • Before performing troubleshooting, inspect the connectors of related circuits.

  • After replacing the Suspension Control ECU with a new one, perform vehicle height offset calibration.

    Click here

PROCEDURE


  1. READ VALUE USING GTS (IG SW Signal)


    1. Turn the power switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    4. Turn the GTS on.

    5. Enter the following menus: Chassis / Air suspension / Data List.

      OK
      The values are as specified in the normal condition column.

      Chassis > Air suspension
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      IG SW Signal IG SW signal ON or OFF

      ON: Power switch on (IG)

      OFF: Power switch off

      		 "OFF" is also displayed for this item when the power switch is on (ACC).

      Chassis > Air suspension > Data List
      Tester Display
      IG SW Signal
      Result
      Result Proceed to
      OK A
      NG B

    B

    REPAIR MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) IG CIRCUIT

    A

  2. CHECK TERMINAL VOLTAGE (IG TERMINAL)


    1. Turn the power switch off.

    2. Disconnect the L105 suspension control ECU connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      L105-8 (IG) - Body ground Power switch off Below 1 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE SUSPENSION CONTROL ECU Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR