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Home >> Suzuki >> 2009 >> Equator Base, 4D Pickup >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (VQ40DE) - (3 Of 5) >> DTC P1564: ASCD Steering Switch >> Diagnosis Procedure
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Diagnosis Procedure

DIAGNOSIS PROCEDURE

Step Action YES NO
CHECK GROUND CONNECTIONS 
  1. Turn ignition switch OFF.
  2. Loosen and retighten three ground screws on the body. Refer to [POWER SUPPLY AND GROUND CIRCUIT CHECK ].
G06441565Courtesy of SUZUKI OF AMERICA CORP.

OK or NG 
GO TO 2. Repair or replace ground connections.
CHECK ASCD STEERING SWITCH CIRCUIT 
  1. With SDT 
    1. Turn ignition switch ON.
    2. Select "MAIN SW", "CANCEL SW", "RESUME/ACC SW" and "SET SW" in "Data list" mode with SDT.
    3. Check each item indication under the following conditions.
G06441566G06441567G06441568Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.

  1. 2) Without SDT 
    1. Turn ignition switch ON.
    2. Check voltage between ECM terminal 99 and ground with pressing each button.
G06441566G06441567G06441568Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.
G06441566G06441567G06441568Courtesy of SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.SUZUKI OF AMERICA CORP.

OK or NG 
GO TO 8. GO TO 3.
CHECK ASCD STEERING SWITCH GROUND CIRCUIT FOR OPEN AND SHORT 
  1. Turn ignition switch OFF.
  2. Disconnect combination switch harness connector.
  3. Disconnect ECM harness connector.
  4. Check harness continuity between combination switch terminal 15 and ECM terminal 67. Refer to WIRING DIAGRAM .

    Continuity should exist. 

  5. Also check harness for short to ground and short to power.

OK or NG 
GO TO 5. GO TO 4.
DETECT MALFUNCTIONING PART 
Check the following.
  • Harness connectors M31, E152
  • Harness connectors E5, F14
  • Combination switch (spiral cable)
  • Harness for open and short between ECM and combination switch
Repair op circuit or short to ground or short to power in harness o connector  
CHECK ASCD STEERING SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
  1. Check harness continuity between ECM terminal 99 and combination switch terminal 14.

    Refer to WIRING DIAGRAM .

    Continuity should exist. 

  2. Also check harness for short to ground and short to power.

OK or NG 
GO TO 7. GO TO 6.
DETECT MALFUNCTIONING PART 
Check the following.
  • Harness connectors M31, E152
  • Combination switch (spiral cable)
  • Harness for open and short between ECM and combination switch
Repair op circuit or short to ground or short to power in harness o connector  
CHECK ASCD STEERING SWITCH 
Refer to [P1564 ASCD STEERING SWITCH ].
OK or NG 
GO TO 8. Replace steering switch.
CHECK INTERMITTENT INCIDENT 
Refer to [SERVICE INFORMATION FOR ELECTRICAL INCIDENT: INTERMITTENT INCIDENT ]
INSPECTION END