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Diagnostic Procedure

DTC U0164:68 (FRONT BODY CONTROL MODULE) DIAGNOSTIC PROCEDURE

Step Inspection Action
1 VERIFY FRONT BODY CONTROL MODULE (FBCM) DTCs AGAIN 
  • Clear front body control module (FBCM) DTCs using the M-MDS.

    (See CLEARING DTC .)

  • Switch the ignition ON (engine off or on) and wait for 5 s or more  .
  • Perform the front body control module (FBCM) DTC inspection using the M-MDS.

    (See DTC INSPECTION .)

  • Is the DTC U0164:68 displayed?
 Yes A malfunction in LIN bus communication line can be considered.
  • Repair or replace the wiring harness between the climate control unit and front body control module (FBCM), then go to the next step.
No Go to Step 9.
2 INSPECT CLIMATE CONTROL UNIT CONNECTOR CONDITION 
 Yes Go to the next step.
No Repair or replace the connector, then go to Step 8.
3 INSPECT FRONT BODY CONTROL MODULE (FBCM) CONNECTOR CONDITION 
  • Disconnect the front body control module (FBCM) connector.
  • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
  • Is the connector normal?
 Yes Go to the next step.
No Repair or replace the connector, then go to Step 8.
4 INSPECT CLIMATE CONTROL UNIT CIRCUIT FOR SHORT TO GROUND 
  • Verify that the climate control unit and front body control module (FBCM) connectors are disconnected.
  • Inspect for continuity between front body control module (FBCM) terminal 2J (vehicle wiring harness side) and body ground.
  • Is there continuity?
 Yes Repair or replace the wiring harness which is shorted to ground, then go to Step 8.
No Go to the next step.
5 INSPECT CLIMATE CONTROL UNIT CIRCUIT FOR SHORT TO POWER SUPPLY 
 Yes Go to the next step.
No Repair or replace the wiring harness which is shorted to power supply, then go to Step 8.
6 INSPECT CLIMATE CONTROL UNIT CIRCUIT FOR OPEN CIRCUIT 
  • Verify that the climate control unit and front body control module (FBCM) connectors are disconnected.
  • Switch the ignition to off.
  • Disconnect the negative battery cable.

    (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)

  • Inspect the wiring harness for continuity between climate control unit terminal K (vehicle wiring harness side) and front body control module (FBCM) terminal 2J (vehicle wiring harness side).
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness which has an open circuit, then go to Step 8.
7 PERFORM DTC INSPECTION AND VERIFY IF MALFUNCTIONING PART IS CLIMATE CONTROL UNIT 
 Yes Replace the climate control unit, then go to the next step.
(See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .)
No Go to Step 9.
8 VERIFY THAT REPAIRS HAVE BEEN COMPLETED 
 Yes Replace the front body control module (FBCM), then go to the next step.
(See FRONT BODY CONTROL MODULE (FBCM) REMOVAL/INSTALLATION .)
No Go to the next step.
9 VERIFY IF OTHER DTCs DISPLAYED 
  • Are any other DTCs displayed?
 Yes Repair the malfunctioning part according to the applicable DTC troubleshooting.
(See DTC TABLE .)
No DTC troubleshooting completed.
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