Diagnostic Procedure

WARNING: This page is about a different car, the 2004 Nissan Titan. However, it is still accessible from the selected car via links, so may be relevant.

CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground three screws on the body.
  
  Fig 1: Locating Ground Screws
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Refer to GROUND INSPECTION .
OK or NG
1. OK: GO TO 2.
2. NG: Repair or replace ground connections.
CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-I
1. Check voltage between ECM terminal 3 and ground under the following conditions with CONSULT-II or tester.
  
  Fig 2: Voltage Chart
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 3: Checking Voltage
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK: GO TO 9.
2. NG: GO TO 3.
CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Disconnect IPDM E/R harness connector E119.
4. Check harness continuity between ECM terminal 3 and IPDM E/R terminal 6.
  Refer to WIRING DIAGRAM .
  1. Continuity should exist.
5. Also check harness for short to ground and short to power.
OK or NG
1. OK: GO TO 5.
2. NG: GO TO 4.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E2, F32
- Harness for open or short between ECM and IPDM E/R
1. Repair open circuit or short to ground or short to power in harness or connectors.
CHECK THROTTLE CONTROL MOTOR RELAY POWER SUPPLY CIRCUIT-I
1. Reconnect all harness connectors disconnected.
2. Turn ignition switch OFF.
3. Check voltage between ECM terminal 104 and ground with CONSULT-II or tester.
  1. Voltage: Battery voltage
    
    Fig 4: Checking Voltage
    Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK: GO TO 8.
2. NG: GO TO 6.
CHECK THROTTLE CONTROL MOTOR RELAY POWER SUPPLY CIRCUIT-II
1. Disconnect ECM harness connector.
2. Disconnect IPDM E/R harness connector E122.
3. Check harness continuity between ECM terminal 104 and IPDM E/R terminal 47.
  Refer to WIRING DIAGRAM .
  
  Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
1. OK: GO TO 7.
2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
CHECK FUSE
1. Disconnect 20A fuse.
2. Check 20A fuse for blown.
OK or NG
1. OK: GO TO 8.
2. NG: Replace 20A fuse.
CHECK INTERMITTENT INCIDENT
Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

OK or NG
1. OK: Replace IPDM E/R. Refer to REMOVAL AND INSTALLATION OF IPDM E/R in IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM) - TITAN article.
2. NG: Repair or replace harness or connectors.
CHECK THROTTLE CONTROL MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN OR SHORT
1. Turn ignition switch OFF.
2. Disconnect electric throttle control actuator harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between the following terminals.
  Refer to WIRING DIAGRAM .
  
  Fig 5: Checking Harness Continuity
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 6: Locating Electric Throttle Control Actuator
  Courtesy of NISSAN MOTOR CO., U.S.A.
5. Also check harness for short to ground and short to power.
OK or NG
1. OK: GO TO 10.
2. NG: Repair or replace.
CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY
1. Remove the intake air duct.
2. Check if foreign matter is caught between the throttle valve and the housing.
  
  Fig 7: Locating Electric Throttle Control Actuator
  Courtesy of NISSAN MOTOR CO., U.S.A.
OK or NG
1. OK: GO TO 11.
2. NG: Remove the foreign matter and clean the electric throttle control actuator inside.
CHECK THROTTLE CONTROL MOTOR
Refer to COMPONENT INSPECTION .

OK or NG
1. OK: GO TO 12.
2. NG: GO TO 13.
CHECK INTERMITTENT INCIDENT
Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

OK or NG
1. OK: GO TO 13.
2. NG: Repair or replace harness or connectors.
REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
1. Replace the electric throttle control actuator.
2. Perform THROTTLE VALVE CLOSED POSITION LEARNING in BASIC DIAGNOSTIC PROCEDURES - TITAN article.
3. Perform IDLE AIR VOLUME LEARNING in BASIC DIAGNOSTIC PROCEDURES - TITAN article.
1. INSPECTION END