PACCAR MX (2004 Emissions) Fault Code: P0493 Fan Speed Control - Incorrect

PACCAR MX (2004 Emissions) Fault Code: P0493 Fan Speed Control - Incorrect

SET CONDITIONS:
The PCI ECU (D420) detects that the actual fan speed is higher than expected.

DIAGNOSTIC CONDITION:
This diagnostic runs every 300 seconds:
1. When the engine has been running for more than 300 seconds
2. When the engine speed is greater than 1000 rpm
3. When the coolant temperature is above 70°C [158°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?
- No, repair successful
- Yes, repair unsuccessful

POSSIBLE CAUSES:
Faulty electronically controlled fan clutch

ADDITIONAL INFORMATION:
1. The negative side coil of the electronically controlled fan clutch (B335) is controlled with the duty cycle by the PCI ECU. When the duty cycle is:
- High, the fan speed is low or decreasing
- Low, the fan speed is high or increasing
2. The fan speed is monitored by the fan clutch internal speed sensor.

If you want to know other articles similar to PACCAR MX (2004 Emissions) Fault Code: P0493 Fan Speed Control - Incorrect you can visit the category DTC TRUCKS.

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