Kohler ECV940 Service Manual page 54

EFI SYSTEM-ELECTRONIC THROTTLE BODY (ETB)
EFI Diagnostic Flow Diagram
START OF TEST
KEY ON
ETB AND
FUEL PUMP CYCLE?
MALFUNCTION INDICATOR
LIGHT ON?
ARE FAULT CODES
PRESENT?
NO
DOES ENGINE START?
NO
CRANK ENGINE.
DOES MIL GO OFF?
YES
KEY OFF AND KEY ON .
1
LISTEN FOR FUEL PUMP
AND ETB.
DOES ETB AND FUEL
PUMP CYCLE ON THEN OFF
AFTER 1–2 SECONDS ?
2
YES
WHILE CRANKING, CHECK
IGNITION SYSTEM
SPARK?
YES
WHILE CRANKING, CHECK
INJECTOR FUEL DELIVERY.
WET SPARK PLUG?
YES
INSTALL IN-LINE PRESSURE
GAUGE AND KEY ON.
FUEL PRESSURE
IN SPECIFICATION?
1. After turning key to OFF, wait 10 seconds before turning to ON to allow ECU to go to sleep.
2. Fuel pump module can be heard or a vibration can be felt to establish pump cycle. Fuel pump module will run for one 4-6 second cycle when
ECU wakes up after being asleep.
54
NO
YES
YES MIL GOES OFF?
YES
NO
NO
REFER TO DIAGNOSTIC AID #5
NO
NO
NO
YES
KohlerEngines.com
PROCEED TO START OF TEST FOR RETEST
REFER TO DIAGNOSTIC AID #1
SYSTEM POWER
REFER TO
FAULT (P) CODE SUMMARY
CLEAR CODES
REFER TO DIAGNOSTIC AID #3
NO
RUN/ON
OPERATE AT VARIOUS SPEED/
LOAD CONDITIONS
ARE FAULT CODES
PRESENT?
NO
END OF TEST
REFER TO DIAGNOSTIC AID #4
CRANKSHAFT POSITION SENSOR
OR
FUEL PUMP
REFER TO DIAGNOSTIC AID #6
IGNITION SYSTEM
REFER TO DIAGNOSTIC AID #7
FUEL SYSTEM ELECTRICAL
REFER TO DIAGNOSTIC AID #8
FUEL SYSTEM
REFER TO DIAGNOSTIC AID #9
BASIC ENGINE
REFER TO FAULT (P)
YES
CODE SUMMARY
CLEAR CODES
REFER TO DIAGNOSTIC
AID #12 ETB
62 690 05 Rev. H