PACCAR MX (2004 Emissions) Fault Code: P1485 EGR Valve Module Temperature – Data Valid but Too High

Description

PACCAR MX (2004 Emissions) Fault Code: P1485 EGR Valve Module Temperature – Data Valid but Too High

SET CONDITIONS:
The EGR valve module (L095) detects that the temperature of the actuator has been above 142?C for more than 30 seconds.

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

CORRESPONDING OBD READINESS MONITOR:
None

RESET CONDITION:
This DTC changes to inactive after the ignition is keyed off for at least 15 seconds and keyed on again, and 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. The ignition is keyed on shortly after a hot engine shutdown.
2. Malfunctioning cooling system. Check the engine cooling system for:
– Low coolant level
– Air in cooling system
– Blocked cooling pipes to the actuator

ADDITIONAL INFORMATION:
1. The temperature is measured on the actuator’s printed circuit board.
2. The actuator motor is switched off and the EGR valve is fully closed (0% position) with this fault active.
3. Engine torque is reduced after 10 hours of engine operation.