Diagnosis Procedure

WARNING: This page is about a different car, the 2012 Nissan Pathfinder. However, it is still accessible from the selected car via links, so may be relevant.

CHECK ECM POWER SUPPLY
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check voltage between ECM terminal 121 and ground with CONSULT or tester.
Voltage: Battery voltage

OK or NG

OK: GO TO 3.

NG: GO TO 2.

Fig 1: Checking Voltage Between ECM Terminal 121 And Ground Using Tester
Courtesy of NISSAN NORTH AMERICA, INC.
DETECT MALFUNCTIONING PART
Check the following.
- IPDM E/R connector E121
- 20 A fuse (No. 53)
- Harness for open or short between ECM and battery
Repair or replace harness or connectors.
CHECK INTERMITTENT INCIDENT
Refer to "INTERMITTENT INCIDENT ".

OK or NG

OK: GO TO 4.

NG: Repair or replace harness or connectors.
PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Erase DTC.
3. Perform DTC Confirmation Procedure. Refer to "DTC CONFIRMATION PROCEDURE ".
4. Is the 1st trip DTC P0603 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: SPECIAL REPAIR REQUIREMENT " (with intelligent key system) or "ECM RE-COMMUNICATING FUNCTION: SPECIAL REPAIR REQUIREMENT " (without intelligent key system).
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