4962 690 05 Rev. H KohlerEngines.com
EFI SYSTEM-ELECTRONIC THROTTLE BODY (ETB)
Fault Code MIL Blinks SPN FMI
Code P0122 10/10/3/3 51 4
Component: Throttle Position Sensor (TPS)
Fault: TPS Circuit Low Voltage or Open
Condition: Open connection, broken wire or faulty
sensor.
Conclusion: TPS Related
● TPS bad or worn internally.
Engine Wiring Harness Related
● Broken or shorted wire in harness.
ECU Black pin 10 to TPS pin 1.
ECU Black pin 12 to TPS pin 3.
ECU Black pin 16 to TPS pin 2.
Throttle Body Related
● Throttle shaft inside TPS worn, broken,
or damaged.
● Throttle plate loose or misaligned.
● Throttle plate bent or damaged
allowing extra airfl ow past, or restricting
movement.
ECU Related
● Circuit providing voltage or ground to
TPS damaged.
● TPS signal input circuit damaged.
Fault Code MIL Blinks SPN FMI
Code P0123 10/10/3/3 51 3
Component: Throttle Position Sensor (TPS)
Fault: TPS Circuit High Voltage
Condition: Shorted connection or faulty sensor.
Conclusion: TPS Sensor Related
● Sensor connector or wiring.
Throttle Body Related
● Throttle shaft or bearings worn/
damaged.
Engine Wiring Harness Related
● ECU pins Black 10, 12 and 16
damaged (wiring, connectors).
● ECU pins Black 10, 12 and 16 routed
near noisy electrical signal (coils,
stator).
● Intermittent 5 volt source from ECU
(pin Black 16).
● ECU-to-harness connection problem.
Fault Code MIL Blinks SPN FMI
Code P0131 10/11/15/10 3056 4
Component: Oxygen Sensor
Fault: O2S 1 Circuit Low Voltage
Condition: Open connection, broken wire or faulty
sensor.
Conclusion: Oxygen Sensor Related
● Sensor connector or wiring problem.
● Sensor contaminated, corroded or
damaged.
● Poor ground path.
● Pin circuit wiring or connectors.
ECU Black pin 10 or 17.
TPS Auto-Learn Incorrect
● Lean condition (check oxygen sensor
signal with VOA and see Oxygen
Sensor).
Engine wiring harness related such as a
cut wire, broken or pinched.
Fault Code MIL Blinks SPN FMI
Code P0132 10/11/15/10 3056 3
Component: Oxygen Sensor
Fault: O2S 1 Circuit High Voltage
Condition: Shorted connection or faulty sensor.
Conclusion: Oxygen Sensor Related
● Sensor connector or wiring problem.
● Sensor contaminated or damaged.
● Poor ground path.
● Pin circuit wiring or connectors.
ECU Black pin 10 or Black pin 17.
Engine Wiring Harness Related
● Diff erence in voltage between sensed
voltage and actual sensor voltage.
● Short in wire harness.