Paccar

PACCAR MX (2004 Emissions) Fault Code: P1870 Crankcase Air Pressure – Data Valid but Too Low

CORRESPONDING OBD READINESS MONITOR:
None

REPAIR VERIFICATION:
1. Clear all DTCs.
2. Test drive or operate the vehicle to meet the diagnostic conditions and set conditions.
3. Did the DTC come back? (Can be pending, inactive or active)
– No, repair successful
– Yes, repair unsuccessful

PACCAR MX (2004 Emissions) Fault Code: P1871 Pressure Before Turbocharger Compressor (Humidity Sensor) – Data Valid but Too Low

CORRESPONDING OBD READINESS MONITOR:
None

REPAIR VERIFICATION:
1. Clear all DTCs.
2. Test drive or operate the vehicle to meet the diagnostic conditions and set conditions.
3. Did the DTC come back? (Can be pending, inactive or active)
– No, repair successful
– Yes, repair unsuccessful

PACCAR MX (2004 Emissions) Fault Code: P1872 Pressure Before Turbocharger Compressor (Humidity Sensor) – Data Valid but Too High

CORRESPONDING OBD READINESS MONITOR:
None

REPAIR VERIFICATION:
1. Clear all DTCs.
2. Test drive or operate the vehicle to meet the diagnostic conditions and set conditions.
3. Did the DTC come back? (Can be pending, inactive or active)
– No, repair successful
– Yes, repair unsuccessful

PACCAR MX (2004 Emissions) Fault Code: P1874 Temperature Before Turbocharger Compressor (Humidity Sensor) – Data Valid but Too High

SET CONDITIONS:
The PCI detects that the temperature before compressor measured by the humidity sensor is higher than expected.

DIAGNOSTIC CONDITION:
This diagnostic runs continuously when the ignition is on.

CORRESPONDING OBD READINESS MONITOR:
None

RESET CONDITION:
This DTC changes to inactive when the fault is no longer detected.

REPAIR VERIFICATION:
1. Clear all DTCs.
2. Test drive or operate the vehicle to meet the diagnostic conditions and set conditions.
3. Did the DTC come back? (Can be pending, inactive or active)
– No, repair successful
– Yes, repair unsuccessful

POSSIBLE CAUSES:
1. An engine starts shortly after a hot engine shut-down
2. Malfunction of the humidity sensor

ADDITIONAL INFORMATION:
1. The humidity sensor (F852) is a smart sensor that communicates with the PCI ECU via E-CAN.
2. The sensor measures the following three properties of the air in the inlet air pipe (before the turbocharger compressor):
– Air temperature
– Air pressure
– Relative humidity

IMPORTANT: The temperature in the inlet pipe can rise significantly when a hot engine is shut-down at high ambient temperatures. When the engine is restarted shortly after the hot engine shut-down, the temperature in the inlet pipe can briefly exceed the threshold, resulting in this DTC. Check DTC freeze frame data parameter ‘Engine running time since ignition on’. If the DTC was activated shortly after a hot shutdown, no repair is needed.

PACCAR MX (2004 Emissions) Fault Code: P1876 Ambient Pressure – Data Valid but Too High

CORRESPONDING OBD READINESS MONITOR:
None

REPAIR VERIFICATION:
1. Clear all DTCs.
2. Test drive or operate the vehicle to meet the diagnostic conditions and set conditions.
3. Did the DTC come back? (Can be pending, inactive or active)
– No, repair successful
– Yes, repair unsuccessful

PACCAR MX (2004 Emissions) Fault Code: P2104 Engine Protection System – Warning Active

SET CONDITIONS:
This DTC becomes active if the DTC from which it originates has been active for a certain time.

RESET CONDITION:
This DTC becomes inactive as soon as the DTC from which it originates has become inactive.

ADDITIONAL INFORMATION:
IMPORTANT: Do not troubleshoot this DTC since it originates from another active DTC.

1. This DTC only activates a warning for the driver.
2. This DTC is part of the engine protection system and can become active simultaneously with an active DTC related to:
– Low oil pressure
– High coolant temperature
– High oil temperature
– High intercooler temperature
– Low coolant level
– Low/high PCI ECU power supply
– High aftertreatment system temperatures

PACCAR MX (2004 Emissions) Fault Code: P2147 Common Rail Pump Unit 1 – Voltage Too Low or Short Circuit to Ground on ECU (D420) Pin (A26)

SET CONDITIONS:
This DTC is set when the ECU detects a lower voltage than expected on the signal or control circuit of the ECU.

DIAGNOSTIC CONDITION:
The diagnostic runs continuously when the ignition is keyed on.

CORRESPONDING OBD READINESS MONITOR:
None

RESET CONDITION:
The DTC changes to inactive after the diagnostic runs and passes.

REPAIR VERIFICATION:
1. Clear all DTCs.
2. Test drive or operate the vehicle to meet the diagnostic conditions and set conditions.
3. Did the DTC come back?
– No, repair successful
– Yes, repair unsuccessful

POSSIBLE CAUSES:
1. The sensor or actuator signal wiring is interrupted.
2. The sensor or actuator signal wiring has a short circuit to ground.
3. A malfunction in the power supply of the sensor or actuator
4. A malfunction of the sensor or actuator

ADDITIONAL INFORMATION:
When this DTC is active:
1. The engine torque is reduced.
2. The engine runs in protection mode.
3. The maximum rail pressure is limited to 1300 bar.

PACCAR MX (2004 Emissions) Fault Code: P2148 Common Rail Pump Unit 1 – Voltage Too High or Short Circuit to Supply on ECU (D420) Pin (A26)

SET CONDITIONS:
This DTC is set when the ECU detects a higher voltage than expected on the signal or control circuit of the ECU.

DIAGNOSTIC CONDITION:
The diagnostic runs continuously when the ignition is keyed on.

CORRESPONDING OBD READINESS MONITOR:
None

RESET CONDITION:
The DTC changes to inactive after the diagnostic runs and passes.

REPAIR VERIFICATION:
1. Clear all DTCs.
2. Test drive or operate the vehicle to meet the diagnostic conditions and set conditions.
3. Did the DTC come back?
– No, repair successful
– Yes, repair unsuccessful

POSSIBLE CAUSES:
1. The sensor or actuator signal wiring has a short circuit to supply.
2. A malfunction of the sensor or actuator

ADDITIONAL INFORMATION:
When this DTC is active:
1. The engine torque is reduced.
2. The engine runs in protection mode.
3. The maximum rail pressure is limited to 1300 bar.

PACCAR MX (2004 Emissions) Fault Code: P2150 Common Rail Pump Unit 2 – Voltage Too Low or Short Circuit to Ground on ECU (D420) Pin (A27)

SET CONDITIONS:
This DTC is set when the ECU detects a lower voltage than expected on the signal or control circuit of the ECU.

DIAGNOSTIC CONDITION:
The diagnostic runs continuously when the ignition is keyed on.

CORRESPONDING OBD READINESS MONITOR:
None

RESET CONDITION:
The DTC changes to inactive after the diagnostic runs and passes.

REPAIR VERIFICATION:
1. Clear all DTCs.
2. Test drive or operate the vehicle to meet the diagnostic conditions and set conditions.
3. Did the DTC come back?
– No, repair successful
– Yes, repair unsuccessful

POSSIBLE CAUSES:
1. The sensor or actuator signal wiring is interrupted.
2. The sensor or actuator signal wiring has a short circuit to ground.
3. A malfunction in the power supply of the sensor or actuator
4. A malfunction of the sensor or actuator

ADDITIONAL INFORMATION:
When this DTC is active:
1. The engine torque is reduced.
2. The engine runs in protection mode.
3. The maximum rail pressure is limited to 1300 bar.