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Diagnostic procedure

DTC P0122 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA HAS BEEN RECORDED 
  • Has FREEZE FRAME DATA been recorded?
Yes Go to next step.
No Record FREEZE FRAME DATA on repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Check for related Technical Service Bulletin(s) repair information availability.
  • Is any related repair information available?
Yes Perform repair or diagnosis according to available repair information.
  • If vehicle is not repaired, go to the next step.
No Go to the next step.
3 CLASSIFY TP SENSOR OR HARNESS MALFUNCTION 
  • Connect WDS or equivalent.
  • Access TP1 PID.
  • Disconnect throttle body connector.
  • Connect a jumper wire between throttle body terminals A and B (wiring harness-side).
  • Is the voltage above 4.9 V? 
Yes Go to the next step.
No Go to Step 5.
4 INSPECT TP SENSOR  Yes Inspect for poor throttle body connector terminal B connection. Repair or replace if necessary, then go to Step 8.
No Replace the throttle body, then go to Step 8.
5 INSPECT POWER SUPPLY CIRCUIT VOLTAGE AT THROTTLE BODY CONNECTOR 
NOTE:
  • If DTC P0107 and P2228 are also retrieved with P0122, go to NO.29 CONSTANT VOLTAGE troubleshooting procedure.
  • Turn the ignition switch to the ON position (Engine off).
  • Measure the voltage at throttle body terminal B (wiring harness-side).
  • Is the voltage within 4.5-5.5 V? 
Yes Go to next step.
No Repair or replace open circuit between throttle body connector terminal B (wiring harness-side) and PCM connector terminal 2K (wiring harness-side). Then, then go to Step 8.
6 VERIFY TP1 SIGNAL CIRCUIT FOR OPEN CIRCUIT 
  • Turn the ignition switch off.
  • Inspect for continuity between throttle body terminal A (wiring harness-side) and PCM terminal 2M (wiring harness-side).
  • Is there continuity?
Yes Go to the next step.
No Repair or replace the harness, then go to Step 8.
7 VERIFY TP1 SIGNAL CIRCUIT FOR SHORT TO GROUND 
  • Inspect for continuity between throttle body terminal A (wiring harness-side) and body ground.
  • Is there continuity?
Yes Repair or replace the harness, then go to the next step.
No Go to the next step.
8 VERIFY TROUBLESHOOTING OF DTC P0122 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Turn the ignition switch to the ON position (Engine off).
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Start the engine and warm it up completely.
  • Is the same DTC present?
Yes Replace the PCM, then go to next step.
(See PCM REMOVAL/INSTALLATION .)
No Go to the next step.
9 VERIFY AFTER REPAIR PROCEDURE  Yes Go to the applicable DTC inspection.
(See DTC TABLE )
No Troubleshooting completed.