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Home >> Suzuki >> 2009 >> Equator Base, 4D Pickup >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (VQ40DE) - (2 Of 5) >> DTC P0603: ECM Power Supply >> Diagnosis Procedure
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Diagnosis Procedure

DIAGNOSIS PROCEDURE

Step Action YES NO
CHECK ECM POWER SUPPLY 
  1. Turn ignition switch OFF.
  2. Disconnect ECM harness connector.
  3. Check voltage between ECM terminal 121 and ground with SDT or tester.
G06441527Courtesy of SUZUKI OF AMERICA CORP.

Voltage: Battery voltage 


OK or NG 
GO TO 3. GO TO 2.
DETECT MALFUNCTIONING PART 
Check the following.
  • 20A fuse (No. 53)
  • IPDM E/R harness connector E121
  • Harness for open or short between ECM and battery
Repair open circuit in harness or connectors.  
CHECK INTERMITTENT INCIDENT 
Refer to [SERVICE INFORMATION FOR ELECTRICAL INCIDENT: INTERMITTENT INCIDENT ]
OK or NG 
GO TO 4. Repair or replace harness or connectors.
PERFORM DTC CONFIRMATION PROCEDURE 
  1. With SDT 
    1. Turn ignition switch ON.
    2. Select "DTC check" mode with SDT.
    3. Touch "Clear".
    4. Perform DTC Confirmation Procedure.  See [P0603 ECM POWER SUPPLY ].
    5. Is the 1st trip DTC P0603 displayed again?
  2. With GST 
    1. Turn ignition switch ON.
    2. Select Service $04 with GST.
    3. Perform DTC Confirmation Procedure.  See [P0603 ECM POWER SUPPLY ].
    4. Is the 1st trip DTC P0603 displayed again?

Yes or No 
GO TO 5. INSPECTION END 
REPLACE ECM 
  1. Replace ECM.
  2. Perform initialization of immobilizer system and registration of all immobilizer system ignition key IDs. Refer to [ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT: SPECIAL REPAIR REQUIREMENT ]
  3. Perform "VIN Registration" in [PROCEDURE AFTER REPLACING ECM ].
  4. Perform "Accelerator Pedal Released Position Learning" in [PROCEDURE AFTER REPLACING ECM ].
  5. Perform "Throttle Valve Closed Position Learning" in [PROCEDURE AFTER REPLACING ECM ].
  6. Perform "Idle Air Volume Learning" in [PROCEDURE AFTER REPLACING ECM ].
INSPECTION END