PACCAR MX (2004 Emissions) Fault Code: P1458 EGR Temperature – Data Erratic, Intermittent, or Incorrect

PACCAR MX (2004 Emissions) Fault Code: P1458 EGR Temperature – Data Erratic, Intermittent, or Incorrect

SET CONDITIONS:
The PCI ECU (D420) detects that measured EGR gas flow temperature differs too much from the expected EGR gas flow temperature for more than 40 seconds.

DIAGNOSTIC CONDITION:
This diagnostic runs:
1. 150 seconds after an engine start
2. When the coolant temperature is above 65?C [149?F] and
3. The engine mode is DOC heating or DPF regeneration or SCR heating or SCR high efficiency or standard or protection.

CORRESPONDING OBD READINESS MONITOR:
EGR system monitor

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 following conditions:
– Corresponding readiness monitor displays ‘Ready’
– Diagnostic conditions are met
– Set conditions are met
3. Did the DTC come back? (Can be pending, inactive or active)
– No, repair successful
– Yes, repair unsuccessful

POSSIBLE CAUSES:
1. Contaminated EGR cooler
2. Extremely high exhaust gas temperatures
3. EGR temperature sensor deviation

ADDITIONAL INFORMATION:
The EGR gas flow temperature is monitored by the EGR temperature sensor (F749).