CAT 3406E (Prefix 1MM or 2WS) Fault Code: 25 PID: SPN: 102 FMI: 7 Boost Pressure not responding

The Engine Control Module (ECM) detects the following conditions:

•Actual boost is less than desired boost by more than 30 kPa (4.4 psi) for more than eight seconds.
•The current for the turbocharger solenoid is greater than 80% of the maximum value.
•Desired boost is not ZERO.
•The ECM has been powered for at least two seconds.

The wastegate solenoid allows the engine to more precisely regulate the boost pressure to the engine. By closing or partially closing the wastegate solenoid, the ECM can increase the boost pressure. Typical wastegates will limit boost pressure to a preset limit. The wastegate solenoid blocks air from reaching the wastegate and allowing boost pressure to increase. Air is routed from the intake manifold to the wastegate solenoid. Then, the air is directed to the wastegate. A bleed orifice allows air to escape, which allows the wastegate to close when the solenoid is closed.

Probable Causes:

1) Wastegate Solenoid Failure
2) Debris in system causing wastegate solenoid failure
3) Air not reaching wastegate solenoid
4) Bleed orifice is blocked
5) Wategate solenoid o-ring failure
6) Wastegate failure
7) ECM Failure