Generac Power Systems GP Series Diagnostic Repair Manual page 38

Section 5 Engine Diagnostic Tests
Fault Indicator Codes
MIL Fault Circuit at Fault
Code Action
Off the Engine
1-1 Shutdown Carbon Monoxide
Monitor
1-2 Shutdown Battery Voltage
1-3 Shutdown Battery Voltage
1-4 Shutdown Fuel Pump &
Field Boost Relay
1-5 Shutdown Fuel Pump &
Field Boost Relay
Fuel Component
2-1 Warning Oxygen Sensor
2-2 Warning Oxygen Sensor
2-3 Shutdown Fuel Injector -
Cylinder 1
2-4 Shutdown Fuel Injector -
Cylinder 1
2-5 Shutdown Fuel Injector -
Cylinder 2
2-6 Shutdown Fuel Injector -
Cylinder 2
Fuel System
3-1 Warning Short-term Fuel
Trim
3-2 Warning Short-term Fuel
Trim
32
Fault Type
CO above limit or input voltage below normal
range
Battery (ECM-1J) or Driver (ECM-1K) voltage
above normal operating range
Battery (ECM-1J) or Driver (ECM-1K) voltage
below normal operating range
No voltage drop detected between relays and
ECM-3L with relay on.
Open or short to ground between relays and
ECM-3L
Sensor output voltage above normal range
(ECM-4J) or Heater circuit shorted to battery
(ECM-2F)
Sensor output voltage below normal range
(ECM-4J) or Heater circuit open or shorted to
ground (ECM-2F)
No voltage drop detected between Injector 1-A
and ECM-3H
No voltage on injector low side (ECM-3H)
No voltage drop detected between Injector 2-A
and ECM-2H
No voltage on injector low side (ECM-2H)
Exceeded maximum fuel correction (added
fuel), engine still running lean
Exceeded minimum fuel correction (subtracted
fuel), engine still running rich
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Verify unit has appropriate ventilation
Check CO monitor connections
Battery voltage regulator (VE+)
overcharging
Check all connections to battery and
battery voltage regulator (VE+)
Battery voltage regulator
undercharging
Check connections for shorts
Faulty relay or pump
Check connections for opens
Faulty relay or pump
Check connections for shorts
Faulty OS
Check connections for opens
Faulty OS
Check connections for shorts
Faulty injector 1
Check connections for opens
Faulty injector 1
Check connections for shorts
Faulty injector 2
Check connections for opens
Faulty injector 2
Check exhaust for holes, cracks, or
leaks
Check fuel pressure
Faulty OS sensor
Fuel pump dirty or faulty
Check fuel lines (clogged, kinked)
Faulty or dirty injectors
Check fuel pressure
Faulty OS sensor
Faulty injector
Faulty fuel pump
Diagnostic Repair Manual