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Home >> Suzuki >> 2009 >> Equator RMZ-4 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (VQ40DE) - (3 Of 5) >> DTC P1805: Brake Switch >> Diagnosis Procedure
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Diagnosis Procedure

DIAGNOSIS PROCEDURE

Step Action YES NO
CHECK STOP LAMP SWITCH CIRCUIT 
  1. Turn ignition switch OFF.
  2. Check the stop lamp when depressing and releasing the brake pedal.
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OK or NG 
GO TO 4. GO TO 2.
CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT 
  1. Disconnect stop lamp switch harness connector.
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  1. 2. Check voltage between stop lamp switch terminal 1 and ground with SDT or tester.
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Voltage: Battery voltage 


OK or NG 
GO TO 4. GO TO 3.
DETECT MALFUNCTIONING PART 
  1. Check the following.
    • 10 A fuse (No. 20)
    • Fuse block (J/B) connector E160
    • Harness for open and short between stop lamp switch and battery
Repair open circuit or short to ground or short to power in harness or connectors.  
CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
  1. Disconnect ECM harness connector.
  2. Disconnect stop lamp switch harness connector.
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  1. 3. Check harness continuity between ECM terminal 101 and stop lamp switch terminal 2. Refer to WIRING DIAGRAM .

    Continuity should exist. 

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

OK or NG 
GO TO 5. Repair open circuit or short to ground or short to power in harness or connectors.
CHECK STOP LAMP SWITCH 
Refer to [P1805 BRAKE SWITCH ].
OK or NG 
GO TO 6. Replace stop lamp switch.
CHECK INTERMITTENT INCIDENT 
Refer to [SERVICE INFORMATION FOR ELECTRICAL INCIDENT: INTERMITTENT INCIDENT ]
INSPECTION END