PACCAR MX (2004 Emissions) Fault Code: P2603 Coolant Pump Speed – Data Valid but Too High

PACCAR MX (2004 Emissions) Fault Code: P2603 Coolant Pump Speed – Data Valid but Too High

SET CONDITIONS:
The PCI ECU (D420) detects that the coolant pump speed is above 5800 rpm.

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:
Malfunctioning coolant pump speed sensor or wiring

ADDITIONAL INFORMATION:
The coolant pump speed is measured by the coolant pump speed sensor (F805).