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Diagnostic procedure

DTC P0480 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA HAS BEEN RECORDED 
  • Has FREEZE FRAME DATA been recorded?
Yes Go to the next step.
No Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Technical Service Bulletin(s) repair information availability.
  • Is any related repair information available?
Yes Perform repair or diagnosis according to the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 INSPECT FAN CONTROL MODULE CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect fan control module connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
Yes Repair or replace the terminal, then go to Step 9.
No Go to the next step.
4 INSPECT FAN CONTROL MODULE SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY 
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage between fan control module terminal B (wiring harness-side) and body ground.
  • Is the voltage B+  ?
Yes Repair or replace the wiring harness for open circuit, then go to Step 9.
No Go to the next step.
5 INSPECT FAN CONTROL MODULE SIGNAL CIRCUIT FOR SHORT TO GROUND 
  • Turn the ignition switch off.
  • Inspect for continuity between fan control module terminal B (wiring harness-side) and body ground.
  • Is there continuity?
Yes Repair or replace the wiring harness for open circuit, then go to Step 9.
No Go to the next step.
6 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
Yes Repair or replace the terminal, then go to Step 9.
No Go to the next step.
7 INSPECT FAN CONTROL MODULE SIGNAL CIRCUIT FOR OPEN CIRCUIT 
  • Inspect for continuity between fan control module terminal B (wiring harness-side) and PCM terminal 1W.
  • Is there continuity?
Yes Go to the next step.
No Repair or replace wiring harness for open circuit, then go to Step 9.
8 INSPECT FAN CONTROL MODULE  Yes Go to the next step.
No Replace the fan control module, then go to the next step.
9 VERIFY TROUBLESHOOTING OF DTC P0480 COMPLETED 
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Start the engine.
  • Turn A/C switch to ON.
  • Is the same DTC present?
Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION .)
No Go to the next step.
10 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC inspection.
(See DTC TABLE )
No Troubleshooting completed.