Paccar

Reason:
Engine Oil Rifle Pressure 1 Sensor Circuit – Voltage Above Normal or Shorted to High Source. High signal voltage detected at the engine oil pressure circuit.

Effect:
None on performance.

Circuit Description:
An engine oil pressure switch or oil pressure sensor is used by the engine control module (ECM) to monitor the lubricating oil pressure. For engines with an oil pressure switch, the switch is normally closed when the engine is not running and open when oil pressure is present. For engines with an oil pressure sensor, the ECM will detect a low signal voltage at operating conditions when the oil pressure is low. The ECM will detect a high signal voltage at operating conditions when the oil pressure is high.

Component Location:
The engine oil pressure sensor is located in the oil rifle.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the engine oil pressure signal voltage was out of range high.

Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic runs and fails.
2) A default value for the engine oil pressure reading is used.

Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
If the oil pressure sensor shares supply and return wires in the engine harness with other sensors, opens and shorts in the engine harness can cause multiple fault codes to be active. Before troubleshooting Fault Code 135, check for multiple faults.

Possible Causes:
1) Open return circuit in the harness, connectors, or sensor
2) A signal circuit shorted to sensor supply or battery voltage

Reason:
Accelerator Pedal or Lever Position Sensor 1 Circuit – Voltage Above Normal or Shorted to High Source. High voltage detected at accelerator pedal position number 1 circuit.

Effect:
The engine will operate in Limp Home mode.

Circuit Description:
The accelerator position sensor is a Hall effect sensor attached to the accelerator pedal. The accelerator position sensor varies the signal voltage to the engine control module (ECM) as the accelerator pedal is depressed and released. Low signal voltage is received by the ECM when the accelerator pedal is at 0 percent. A high signal voltage is received by the ECM when the accelerator pedal is at 100 percent. The accelerator pedal position circuit contains an accelerator pedal position 5 volt supply, accelerator pedal position return, and accelerator pedal position signal.

The accelerator pedal contains two position sensors. These position sensors are used to measure the throttle position. Both position sensors receive a 5 volt supply from the ECM. A corresponding signal voltage based on the position of the accelerator pedal is then received from the ECM. The signal voltage for accelerator position 1 is twice as much as the signal voltage from the accelerator position 2.

Component Location:
The accelerator pedal or lever position sensor is mounted to the accelerator pedal assembly. Refer to the OEM service manual

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the accelerator pedal signal voltage was out of range high.

Action Taken When the Fault Code is Active:
The ECM logs the fault code immediately when the diagnostic runs and fails.

Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults.

Shop Talk:
Newer engines use two throttle position sensors to determine the throttle position. Older throttle pedals used a single throttle position sensor and an idle validation switch. If Fault Codes 1359 and 1241 are active when the accelerator pedal is in the idle position, and Fault Code 1359 goes inactive, and Fault Code 1239 goes active when the throttle is depressed, the incorrect throttle pedal has been installed in the vehicle. A throttle pedal with two acceleration position sensors must be installed.

If troubleshooting an intermittent accelerator problem:
The accelerator pedal or lever position sensor signal voltage can be monitored with INSITE™ electronic service tool, while flexing the harness to locate the intermittent connection. Intermittent connections will show up as abrupt changes in signal voltage displayed by INSITE™ electronic service tool.

NOTE: The three wires in the accelerator position sensor circuit must be twisted together.

Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring supplied by the OEM.

Possible Causes:
1) Accelerator pedal or lever position signal circuit shorted to battery or (+) 5 volt supply
2) Open accelerator pedal return circuit in the harness or connections
3) Accelerator supply shorted to battery
4) Malfunctioning accelerator pedal or lever position sensor.

Reason:
Accelerator Pedal or Lever Position Sensor 1 Circuit – Voltage Below Normal or Shorted to Low Source. Low voltage detected at accelerator pedal position number 1 signal circuit.

Effect:
The engine will operate in Limp Home mode

Circuit Description:
The accelerator position sensor is a Hall effect sensor attached to the accelerator pedal. The accelerator position sensor varies the signal voltage to the engine control module (ECM) as the accelerator pedal is depressed and released. Low signal voltage is received by the ECM when the accelerator pedal is at 0 percent. A high signal voltage is received by the ECM when the accelerator pedal is at 100 percent. The accelerator pedal position circuit contains an accelerator pedal position 5 volt supply, accelerator pedal position return, and accelerator pedal position signal.

The accelerator pedal contains two position sensors. These position sensors are used to measure the throttle position. Both position sensors receive a 5 volt supply from the ECM. A corresponding signal voltage based on the position of the accelerator pedal is then received from the ECM. The signal voltage for accelerator position 1 is twice as much as the signal voltage from the accelerator position 2.

Component Location:
The accelerator pedal or lever position sensor is mounted to the accelerator pedal assembly. Refer to the OEM service manual

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the accelerator pedal signal voltage was out of range low.

Action Taken When the Fault Code is Active:
The ECM logs the fault code immediately when the diagnostic runs and fails.

Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults.

Shop Talk:
Newer engines use two throttle position sensors to determine the throttle position. Older throttle pedals used a single throttle position sensor and an idle validation switch. If Fault Codes 1359 and 1241 are active when the accelerator pedal is in the idle position, and Fault Code 1359 goes inactive, and Fault Code 1239 goes active when the throttle is depressed, the incorrect throttle pedal has been installed in the vehicle. A throttle pedal with two acceleration position sensors must be installed.

The accelerator pedal or lever position sensor signal voltage can be monitored with INSITE™ electronic service tool, while flexing the harness to locate the intermittent connection. Intermittent connections will show up as abrupt changes in signal voltage displayed by INSITE™ electronic service tool.

NOTE: The three wires in the accelerator position sensor circuit must be twisted together.

Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring supplied by the OEM.

Possible Causes:
1) Accelerator pedal or lever position signal shorted to engine ground or return wires in the
2) OEM harness or sensor
3) Damaged accelerator pedal or lever position sensor
4) Open circuit in the accelerator signal, supply, or return wire in the harness or connectors

Reason:
Engine Oil Rifle Pressure 1 Sensor Circuit – Voltage Below Normal or Shorted to Low Source. Low signal voltage or open circuit detected at the engine oil pressure circuit.

Effect:
None on performance.

Circuit Description:
An engine oil pressure switch or oil pressure sensor is used by the engine control module (ECM) to monitor the lubricating oil pressure. For engines with an oil pressure switch, the switch is normally closed when the engine is not running and open when oil pressure is present. For engines with an oil pressure sensor, the ECM will detect a low signal voltage at operating conditions when the oil pressure is low. The ECM will detect a high signal voltage at operating conditions when the oil pressure is high.

Component Location:
The engine oil pressure sensor is located in the oil rifle.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the engine oil pressure signal voltage was out of range low.

Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic runs and fails.
2) A default value for the engine oil pressure reading is used.

Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
If the oil pressure sensor shares supply and return wires in the engine harness with other sensors, opens and shorts in the engine harness can cause multiple fault codes to be active. Before troubleshooting Fault Code 141, check for multiple faults.

Possible Causes:
1) Signal circuit open or shorted to ground in the engine harness or sensor
2) Supply wire open or shorted to ground

Reason:
High Engine Temperature (HET) Shutdown Relay Driver Diagnostic Has Dectected An Error – Condition Exists

Effect:
The high engine temperature shutdown lamp will not turn on.

Circuit Description:
The high engine temperature shutdown lamp will indicate when the engine has reached a most severe level high coolant or intake manifold temperature. Fault Code 151 or 155 will trigger the high engine temperature shutdown lamp.

Component Location:
Refer to the OEM service manual for lamp location

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected an open on the lamp circuit.

Action Taken When the Fault Code is Active:
The ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic runs and fails.

Conditions for Clearing the Fault Code:
1) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults.

Shop Talk:
N/A

Possible Causes:
1) Open signal circuit or shorted to voltage source.
2) A signal shorted to ground in the harness
3) Open signal circuit in the OEM harness, connectors, or sensor

Reason:
High Engine Temperature (HET) Shutdown Relay Driver Diagnostic Has Dectected An Error – Condition Exists

Effect:
The high engine temperature shutdown lamp will not turn on.

Circuit Description:
The high engine temperature shutdown lamp will indicate when the engine has reached a most severe level high coolant or intake manifold temperature. Fault Code 151 or 155 will trigger the high engine temperature shutdown lamp.

Component Location:
Refer to the OEM service manual for lamp location

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected an open on the lamp circuit.

Action Taken When the Fault Code is Active:
The ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic runs and fails.

Conditions for Clearing the Fault Code:
1) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults.

Shop Talk:
N/A

Possible Causes:
1) Open signal circuit or shorted to voltage source.
2) A signal shorted to ground in the harness
3) Open signal circuit in the OEM harness, connectors, or sensor

Reason:
Engine Oil Rifle Pressure – Data Valid But Below Normal Operational Range – Moderately Severe Level. Engine oil pressure signal indicates engine oil pressure is below the engine protection warning limit.

Effect:
Possible reduced engine performance.

Circuit Description:
An engine oil pressure switch or oil pressure sensor is used by the engine control module (ECM) to monitor the lubricating oil pressure. For engines with an oil pressure switch, the switch is normally closed when the engine is not running and open when oil pressure is present. For engines with an oil pressure sensor, the ECM will detect a low signal voltage at operating conditions when the oil pressure is low. The ECM will detect a high signal voltage at operating conditions when the oil pressure is high.

Component Location:
The engine oil pressure sensor is located in the oil rifle.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position and the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the engine oil pressure was less than the engine protection limits for more than 5 seconds.

Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic runs and fails.
2) The torque output of the engine will be reduced.

Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
This fault code goes active when the engine oil pressure drops below the engine protection limit. Troubleshoot the engine for low oil pressure

Possible Causes:
1) Bad ECM
2) Inactive fault codes

Reason:
Engine Oil Rifle Pressure – Data Valid But Below Normal Operational Range – Moderately Severe Level. Engine oil pressure signal indicates engine oil pressure is below the engine protection warning limit.

Effect:
Possible reduced engine performance.

Circuit Description:
An engine oil pressure switch or oil pressure sensor is used by the engine control module (ECM) to monitor the lubricating oil pressure. For engines with an oil pressure switch, the switch is normally closed when the engine is not running and open when oil pressure is present. For engines with an oil pressure sensor, the ECM will detect a low signal voltage at operating conditions when the oil pressure is low. The ECM will detect a high signal voltage at operating conditions when the oil pressure is high.

Component Location:
The engine oil pressure sensor is located in the oil rifle.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position and the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the engine oil pressure was less than the engine protection limits for more than 5 seconds.

Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp immediately when the diagnostic runs and fails.
2) The torque output of the engine will be reduced.

Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
This fault code goes active when the engine oil pressure drops below the engine protection limit. Troubleshoot the engine for low oil pressure

Possible Causes:
1) Faulty ECM
2) Damaged engine coolant temperature sensor and connector pins
3) Faulty sensor resistance
4) Inactive fault codes
5) Faulty engine harness
6) Open circuit in the engine harness
7) Pin-to-pin short circuit in the engine harness

Reason:
Engine Coolant Temperature 1 Sensor Circuit – Voltage Above Normal or Shorted to High Source. High signal voltage or open circuit detected at engine coolant temperature circuit.

Effect:
Fan will stay ON if controlled by the engine control module (ECM).

Circuit Description:
The coolant temperature sensor is a variable resistor sensor and is used to measure the temperature of the coolant of the engine. The engine control module (ECM) supplies 5 volts to the coolant temperature signal circuit. The ECM monitors the change in voltage caused by changes in the resistance of the sensor to determine the coolant temperature.

Component Location:
The engine coolant temperature sensor is located on the thermostat housing.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the engine coolant temperature signal voltage was out of range high.

Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.
2) A default value is used for the engine coolant temperature reading.

Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
The engine coolant temperature sensor shares return wires in the engine harness with other sensors. An open return can cause multiple fault codes to be active. Before troubleshooting Fault Code 144, check for multiple fault codes.

Possible Causes:
1) Open return circuit in the harness, connectors, or sensor
2) Open signal circuit or shorted to a voltage source.
3) Malfunctioning engine coolant temperature sensor