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Diagnostic Procedure

DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Service Bulletins and/or on-line 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.
2 INSPECT AMBIENT TEMPERATURE SENSOR CONNECTOR CONDITION 
  • Switch the ignition off.
  • Disconnect the ambient temperature sensor connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 7.
No Go to the next step.
3 INSPECT AMBIENT TEMPERATURE SENSOR 
 Yes Replace the ambient temperature sensor, then go to Step 7.
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .)
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .)
No Go to the next step.
4 INSPECT AMBIENT TEMPERATURE SENSOR SIGNAL CIRCUIT FOR SHORT TO GROUND 
  • Verify that the ambient temperature sensor connector is disconnected.
  • Inspect for continuity between ambient temperature sensor terminal A (wiring harness-side) and body ground.
  • Is there continuity?
 Yes If the short to ground circuit could be detected in the wiring harness:
  • Refer to the wiring diagram and verify whether or not there is a common connector between ambient temperature sensor terminal A and PCM terminal 2I.

    If there is a common connector: 

    • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
    • Repair or replace the malfunctioning part.

    If there is no common connector: 

    • Repair or replace the wiring harness which has a short to ground.

If the short to ground circuit could not be detected in the wiring harness:

Go to Step 7.
No Go to the next step.
5 INSPECT PCM CONNECTOR CONDITION 
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 7.
No Go to the next step.
6 INSPECT AMBIENT TEMPERATURE SENSOR SIGNAL CIRCUIT AND GROUND CIRCUIT FOR SHORT TO EACH OTHER 
  • Verify that the ambient temperature sensor and PCM connectors are disconnected.
  • Inspect for continuity between ambient temperature sensor terminals A and B (wiring harness-side).
  • Is there continuity?
 Yes Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Ambient temperature sensor terminal A-PCM terminal 2I
  • Ambient temperature sensor terminal B-PCM terminal 2AJ

If there is a common connector: 
  • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to each other.
  • Repair or replace the malfunctioning part.

If there is no common connector: 
  • Repair or replace the wiring harness which has a short to each other.

Go to the next step.
No Go to the next step.
7 VERIFY DTC TROUBLESHOOTING COMPLETED 
  • Always reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS.

    (See AFTER REPAIR PROCEDURE .)

  • Start the engine and warm it up completely.
  • Perform the KOEO or KOER self test.

    (See KOEO/KOER SELF TEST .)

  • Is the same DTC present?
 Yes Repeat the inspection from Step 1.

Go to the next step.
No Go to the next step.
8 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No DTC troubleshooting completed.
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