Paccar

PACCAR MX (2004 Emissions) Fault Code: U17A3 Accelerator Pedal Sensor 2 Duty Cycle – Data Valid but Too High on ECU (D420) Pin (B45)

SET CONDITIONS:
The PCI ECU (D420) detects that the duty cycle of accelerator pedal position sensor 2 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. To validate the repair, monitor the accelerator pedal sensors with the diagnostic service tool.

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:
Faulty accelerator pedal or wiring

ADDITIONAL INFORMATION:
The accelerator pedal position is determined by two sensors (1 and 2) inside the accelerator pedal. The sensor outputs are PWM signals at a fixed frequency of 180 to 220 Hz. Sensor signals 1 and 2 are reversed compared to each other, meaning that by pressing the accelerator more, sensor 1 shows a decreasing PWM signal and sensor 2 shows an increasing PWM signal. The PCI ECU monitors both sensors separately and together.

PACCAR MX (2004 Emissions) Fault Code: U17A4 Accelerator Pedal Sensor 2 Duty Cycle – Data Valid but Too Low on ECU (D420) Pin (B45)

SET CONDITIONS:
The PCI ECU (D420) detects that the duty cycle of accelerator pedal position sensor 2 is lower 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. To validate the repair, monitor the accelerator pedal sensors with the diagnostic service tool.

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:
Faulty accelerator pedal or wiring

ADDITIONAL INFORMATION:
The accelerator pedal position is determined by two sensors (1 and 2) inside the accelerator pedal. The sensor outputs are PWM signals at a fixed frequency of 180 to 220 Hz. Sensor signals 1 and 2 are reversed compared to each other, meaning that by pressing the accelerator more, sensor 1 shows a decreasing PWM signal and sensor 2 shows an increasing PWM signal. The PCI ECU monitors both sensors separately and together.

PACCAR MX (2004 Emissions) Fault Code: U17A5 Accelerator Pedal 2 Frequency – Data Valid but Too High on ECU (D420) Pin (B45)

SET CONDITIONS:
The PCI ECU (D420) detects that the frequency of accelerator pedal position sensor 2 is more than 220 Hz.

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. To validate the repair, monitor the accelerator pedal sensors with the diagnostic service tool.

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:
Faulty accelerator pedal or wiring

ADDITIONAL INFORMATION:
The accelerator pedal position is determined by two sensors (1 and 2) inside the accelerator pedal. The sensor outputs are PWM signals at a fixed frequency of 180 to 220 Hz. Sensor signals 1 and 2 are reversed compared to each other, meaning that by pressing the accelerator more, sensor 1 shows a decreasing PWM signal and sensor 2 shows an increasing PWM signal. The PCI ECU monitors both sensors separately and together.

PACCAR MX (2004 Emissions) Fault Code: U17A6 Accelerator Pedal 2 Frequency – Data Valid but Too Low on ECU (D420) Pin (B45)

SET CONDITIONS:
The PCI ECU (D420) detects that the frequency of accelerator pedal position sensor 2 is less than 180 Hz.

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. To validate the repair, monitor the accelerator pedal sensors with the diagnostic service tool.

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:
Faulty accelerator pedal or wiring

ADDITIONAL INFORMATION:
The accelerator pedal position is determined by two sensors (1 and 2) inside the accelerator pedal. The sensor outputs are PWM signals at a fixed frequency of 180 to 220 Hz. Sensor signals 1 and 2 are reversed compared to each other, meaning that by pressing the accelerator more, sensor 1 shows a decreasing PWM signal and sensor 2 shows an increasing PWM signal. The PCI ECU monitors both sensors separately and together.

PACCAR MX (2004 Emissions) Fault Code: U17A7 Accelerator Pedal – Sensor 1 and 2 Synchronization Malfunction

SET CONDITIONS:
The PCI ECU (D420) detects that the accelerator pedal position sensor 1 or 2 does not correspond to the calculated accelerator pedal position.

DIAGNOSTIC CONDITION:
This diagnostic runs continuously when the ignition is on, but not during engine start-up.

CORRESPONDING OBD READINESS MONITOR:
None

RESET CONDITION:
This DTC changes to inactive when the fault is no longer detected. To validate the repair, monitor the accelerator pedal sensors with the diagnostic service tool.

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:
Faulty accelerator pedal or wiring

ADDITIONAL INFORMATION:
The accelerator pedal position is determined by two sensors (1 and 2) inside the accelerator pedal. The sensor outputs are PWM signals at a fixed frequency of 180 to 220 Hz. Sensor signals 1 and 2 are reversed compared to each other, meaning that by pressing the accelerator more, sensor 1 shows a decreasing PWM signal and sensor 2 shows an increasing PWM signal. The PCI ECU monitors both sensors separately and together.

PACCAR MX (2004 Emissions) Fault Code: U17A8 Accelerator Pedal – Malfunction

SET CONDITIONS:
The PCI ECU (D420) detects that DTCs are active on both accelerator pedal position sensors.

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. To validate the repair, monitor the accelerator pedal sensors with the diagnostic service tool.

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:
Faulty accelerator pedal or wiring

ADDITIONAL INFORMATION:
The accelerator pedal position is determined by two sensors (1 and 2) inside the accelerator pedal. The sensor outputs are PWM signals at a fixed frequency of 180 to 220 Hz. Sensor signals 1 and 2 are reversed compared to each other, meaning that by pressing the accelerator more, sensor 1 shows a decreasing PWM signal and sensor 2 shows an increasing PWM signal. The PCI ECU monitors both sensors separately and together.

PACCAR MX (2004 Emissions) Fault Code: U17A9 Accelerator Pedal Operation – Data Erratic, Intermittent or Incorrect

SET CONDITIONS:
The PCI ECU (D420) detects that the accelerator pedal is depressed above 2.6% while no driver is present.

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. To validate the repair, monitor the accelerator pedal sensors with the diagnostic service tool.

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:
Faulty accelerator pedal or wiring

ADDITIONAL INFORMATION:
1. The PCI ECU is able to detect if a driver is present in the vehicle, based on the accelerator pedal, foot brake pedal and vehicle speed inputs.

2. The accelerator pedal position is determined by two sensors (1 and 2) inside the accelerator pedal. The sensor outputs are PWM signals at a fixed frequency of 180 to 220 Hz. Sensor signals 1 and 2 are reversed compared to each other, meaning that by pressing the accelerator more, sensor 1 shows a decreasing PWM signal and sensor 2 shows an increasing PWM signal. The PCI ECU monitors both sensors separately and together.

PACCAR MX (2004 Emissions) Fault Code: U17B0 Water in Fuel Drain Control – Short Circuit to Supply on ECU (D420) Pin (A40)

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?
– No, repair successful
– Yes, repair unsuccessful

PACCAR MX (2004 Emissions) Fault Code: U17B1 Water in Fuel Drain Control – Short Circuit to Ground on ECU (D420) Pin (A40)

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?
– No, repair successful
– Yes, repair unsuccessful