Possible causes

– Exhaust leak
– Improperly installed or loose Exhaust Gas Temperature (EGT)
– Low engine compression
– Corroed fuel injector
– Water in the fuel system

When is the code detected?

The P2459 will set if the Engine Control Module (ECM) detects that the average time between completed regenerations is less than a calibrated threshold.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P2459 FORD Description

The particulates in the exhaust gases are collected by the Diesel Particulate Filter (DPF). When the filter becomes saturated with particulates, they are incinerated by a regeneration process. The regeneration process increases the exhaust gas temperature, warning the Diesel Oxidation Catalyst (DOC) first, the warning the DPF. The Engine Control Module (ECM) monitors the system with inputs from two Exhaust Gas Temperature (EGT) sensors 1 and 2 and the exhaust differential pressure sensor.