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Diagnosis Procedure

WARNING: This page is about a different variant/trim than selected.

PERFORM IDLE AIR VOLUME LEARNING
Perform "IDLE AIR VOLUME LEARNING ".

Is Idle Air Volume Learning carried out successfully?

Yes or No

Yes: GO TO 2.

No: Follow the instruction of Idle Air Volume Learning.
CHECK INTAKE SYSTEM
Check for the cause of intake air volume lacking. Refer to the following.
- Crushed intake air passage
- Intake air passage clogging
  OK or NG
  
  OK: GO TO 3.
  
  NG: Repair or replace malfunctioning part
CHECK FUEL INJECTION SYSTEM FUNCTION
Perform "DTC CONFIRMATION PROCEDURE " for DTC P0171.

OK or NG

OK: GO TO 4.

NG: Go to "DIAGNOSIS PROCEDURE " for DTC P0171.
PERFORM DTC CONFIRMATION PROCEDURE
1. Erase DTC.
2. Perform DTC Confirmation Procedure .
  See "DTC CONFIRMATION PROCEDURE ".
3. Is the 1st trip DTC P1421 displayed again?
  Yes or No
  
  Yes: GO TO 5.
  
  No: INSPECTION END
REPLACE ECM
1. Replace ECM.
2. Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs.
  Refer to "ECM RE-COMMUNICATING FUNCTION ".
3. Perform "VIN REGISTRATION ".
4. Perform "ACCELERATOR PEDAL RELEASED POSITION LEARNING ".
5. Perform "THROTTLE VALVE CLOSED POSITION LEARNING ".
6. Perform "IDLE AIR VOLUME LEARNING ".
  INSPECTION END