Paccar

PACCAR MX (2004 Emissions) Fault Code: P153C Crankcase Ventilation Module Rotor Speed – Data Valid but Too High

SET CONDITIONS:
The crankcase ventilation speed sensor value > 15,000 rpm

DIAGNOSTIC CONDITION:
This diagnostic runs when the time since key on > 60 seconds and the engine speed > 500 rpm

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:
Malfunction of the crankcase ventilation speed sensor

ADDITIONAL INFORMATION:
Overspeed of the crankcase ventilation rotor detected.

PACCAR MX (2004 Emissions) Fault Code: P1560 Coolant Level – Data Valid but Too Low, Moderately Severe

SET CONDITIONS:
The PCI ECU (D420) detects that the coolant level is 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?
– No, repair successful
– Yes, repair unsuccessful

POSSIBLE CAUSES:
Faulty coolant surge tank float/level sensor

PACCAR MX (2004 Emissions) Fault Code: P1563 PCI ECU Power Supply – Data Valid but Too Low, Most Severe

SET CONDITIONS:
The PCI ECU (D420) detects that the power supply has dropped to less than 6 V.

DIAGNOSTIC CONDITION:
This diagnostic runs continuously after starting and running the engine.

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. Alternator malfunctioning
2. PCI ECU power supply connections
3. Defective battery

ADDITIONAL INFORMATION:
1. For this diagnostic, the PCI ECU monitors its power supply only during engine operation to detect a running voltage drain-down. It does not detect a cranking voltage drain-down.

2. Engine torque is reduced with this DTC active.

PACCAR MX (2004 Emissions) Fault Code: P1564 Fuel Pressure – Data Erratic, Intermittent or Incorrect, at Ignition On

SET CONDITIONS:
The PCI ECU (D420) detects that the fuel pressure is 1.2 bar [17 psi] or more for more than 5 seconds.

DIAGNOSTIC CONDITION:
This diagnostic runs when the engine is not running and when the ignition is keyed on after it has been off for more than 60 minutes.

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. Fuel pressure sensor deviation
2. Faulty fuel pressure sensor wiring

ADDITIONAL INFORMATION:
1. For this diagnostic, the low-pressure fuel pressure is monitored when the engine is not running.
2. The low-pressure fuel pressure is measured by the fuel pressure sensor (F801).

PACCAR MX (2004 Emissions) Fault Code: P1565 Idle Speed – Differs From the Target Idle Speed

SET CONDITIONS:
The PCI ECU (D420) detects that the measured idle speed:
1. Differs on average more than 70 rpm for more than 5 seconds from the expected idle speed, four times consecutively or
2. Is above 975 rpm for more than 22 seconds or
3. Is below 325 rpm for more than 22 seconds

DIAGNOSTIC CONDITION:
The diagnostic runs when the engine operating state is Idle.

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

POSSIBLE CAUSES:
1. PTO controls incorrectly using TSC1 messaging
2. Heavy load on engine during idling
3. Fuel system failure

ADDITIONAL INFORMATION:
The idle speed governor function in the PCI ECU controls the idle speed. This diagnostic monitors that the actual idle speed does not deviate too much from the expected governed idle speed.

PACCAR MX (2004 Emissions) Fault Code: P1566 Idle Speed Control – Incorrect

SET CONDITIONS:
The PCI ECU (D420) detects that the actual fuel quantity during idling:
1. Differs on average more than 40 mg/stroke for more than 5 seconds from the requested fuel quantity, four times consecutively or
2. Is above 75 mg/stroke for more than 24 seconds or
3. Is below 8 mg/stroke for more than 24 seconds

DIAGNOSTIC CONDITION:
The diagnostic runs when the engine operating state is Idle.

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

POSSIBLE CAUSES:
1. Heavy load on engine during idling
2. fuel system failure
3. External fuel supply source

ADDITIONAL INFORMATION:
The idle speed governor function in the PCI ECU controls the idle speed. This diagnostic monitors that the actual fuel quantity during idling does not deviate too much from the requested fuel quantity during idling.

PACCAR MX (2004 Emissions) Fault Code: P156E Vehicle Speed Sensor – Voltage Too Low or Short Circuit to Ground on ECU (D420) Pin (B12)

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: P156F Vehicle Speed Sensor – Voltage Too High or Short Circuit to Supply on ECU (D420) Pin (B12)

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