What does fault code ECM-P02FA78 mean?

Diagnostic fault code details for ECM-P02FA78 (Volvo C30 (2007–2013), Volvo S40 (2004–2013), Volvo S60 (2011–)). Repair service at OBD Tuning.

VOLVO

ECM-P02FA78 - Diesel Intake Air Flow Position Sensor Minimum/Maximum Stop Performance. Mechanical Failures. Alignment or adjustment incorrect

System

Engine Control Module (ECM)

Volvo models this fault code applies to

Applies to the following models:

9 models

C30 (2007–2013), S40 (2004–2013), S60 (2011–), S80 (2007–), V40 (2013–), V40 Cross Country (2013–), V50 (2004–2013), V60 (2011–), V70 (2008–)

Show models by year and engine (9)

What does this fault code mean?

The fault is mechanical and concerns the setting of the intake air control valve. The engine control module (ECM) checks the learned limits of the valve for the closed and open positions. If the limit for the open position is outside the permitted range, the fault code is stored. The cause may be a valve that sticks because of dirt, or a damaged valve.

Possible causes

Sticking control valve due to dirt or contamination
Damaged control valve in the intake air inlet

What you can do

1Read the fault code, clear it and check whether it returns after a drive
2Check that the control valve is not dirty and does not stick when moved by hand
3Check that the fuses are intact; their locations are shown in the owner's manual or on the fuse box cover
4If you have a diagnostic tool: read the valve's learned limits in live data and see whether the limit for the open position is unreasonable
5Have a workshop with diagnostic equipment redo the setting and check the valve; replace it if it is damaged

Symptoms you may notice1

No noticeable symptoms for the driver

General guidance for car owners. Diagnosis on the car can point to a different cause.