Paccar

PACCAR MX (2004 Emissions) Fault Code: P0335 Crankshaft Speed Signal – Disturbed or No Signal During Engine Operation

SET CONDITIONS:
The PCI ECU (D420) detects that one or more holes in the flywheel are not detected within one crankshaft revolution.

DIAGNOSTIC CONDITION:
This diagnostic runs continuously when the engine is running.

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?
– No, repair successful
– Yes, repair unsuccessful

POSSIBLE CAUSES:
1. No crankshaft sensor signal
2. Faulty crankshaft sensor signal
3. Damaged flywheel

ADDITIONAL INFORMATION:
1. Crankshaft sensor (F552) is used to determine the crankshaft speed and position.
2. It is possible that the camshaft sensor (F558) is used as backup to run the engine.
3. Engine torque is reduced.

PACCAR MX (2004 Emissions) Fault Code: P0340 Camshaft Speed Signal – Disturbed or no Signal During Engine Operation

SET CONDITIONS:
The PCI ECU (D420) detects that one or more teeth of the camshaft sensor tone wheel are not detected within one crankshaft revolution.

DIAGNOSTIC CONDITION:
This diagnostic runs continuously when the engine is running.

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?
– No, repair successful
– Yes, repair unsuccessful

POSSIBLE CAUSES:
1. No camshaft sensor signal
2. Faulty camshaft sensor signal
3. Damaged pulse ring

ADDITIONAL INFORMATION:
1. Camshaft sensor (F558) is used to determine the position of the engine (cylinder detection).
2. Engine torque is reduced.

PACCAR MX (2004 Emissions) Fault Code: P0341 Camshaft Speed Signal – Out of Range During Engine Operation

SET CONDITIONS:
The PCI ECU (D420) detects that the camshaft sensor signal is disturbed or intermittent.

DIAGNOSTIC CONDITION:
This diagnostic runs continuously when the engine is running.

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?
– No, repair successful
– Yes, repair unsuccessful

POSSIBLE CAUSES:
1. Faulty camshaft sensor signal
2. Faulty camshaft sensor
3. Damaged pulse ring

ADDITIONAL INFORMATION:
1. Camshaft sensor (F558) is used to determine the position of the engine (cylinder detection).
2. Engine torque is reduced.

PACCAR MX (2004 Emissions) Fault Code: P0407 EGR Pressure Difference – Voltage Too Low or Short Circuit to Ground on ECU (D420) Pin (C80)

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:
Multiple sensor related voltage-too-low DTCs can indicate a malfunction within a 5-V sensor power supply circuit of the PCI ECU.

PACCAR MX (2004 Emissions) Fault Code: P0408 EGR Pressure Difference – Voltage Too High or Short Circuit to Supply on ECU (D420) Pin (C80)

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

PACCAR MX (2004 Emissions) Fault Code: P040B EGR Temperature – Data Erratic, Intermittent or Incorrect, at Ignition On

SET CONDITIONS:
The PCI ECU (D420) detects that the measured EGR temperature sensor differs more than 3°C [5.4°F] from the average of other temperature sensor readings on the engine for more than 5 seconds (after the ignition has been keyed off for at least 8 hours).

DIAGNOSTIC CONDITION:
This diagnostic runs:
1. When the ignition has been keyed off continuously for at least 8 hours
2. Difference between the coolant and ambient temperature is less than 15°C [59°F]
3. Ambient temperature is more than -20°C [-4°F]

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:
EGR temperature sensor deviation

ADDITIONAL INFORMATION:
For this diagnostic, the EGR temperature sensor (F749) reading is compared with an average of other temperature sensors on the engine after the ignition has been keyed off for at least 8 hours.

PACCAR MX (2004 Emissions) Fault Code: P040C EGR Temperature – Voltage Too Low or Short Circuit to Ground on ECU (D420) Pin (C9)

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:
Multiple sensor related voltage-too-low DTCs can indicate a malfunction within a 5-V sensor power supply circuit of the PCI ECU.

PACCAR MX (2004 Emissions) Fault Code: P040D EGR Temperature – Voltage Too High or Short Circuit to Supply on ECU (D420) Pin (C9)

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

PACCAR MX (2004 Emissions) Fault Code: P0471 Exhaust Gas Pressure Before Turbine – Data Erratic, Intermittent or Incorrect, at Ignition On

SET CONDITIONS:
The PCI ECU (D420) detects that the measured pressure before turbine sensor reading differs more than 0.36 bar [5.2 PSI] from the average of other engine pressure sensor readings for more than five seconds.

DIAGNOSTIC CONDITION:
This diagnostic runs when the ignition is switched on (NO engine start) and the ambient temperature is more than -20°C [-4°F].

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:
Pressure sensor before turbine deviation

ADDITIONAL INFORMATION:
For this diagnostic, the pressure sensor before turbine (F826) reading is compared with an average of other engine pressure sensor readings.