S60 L5-2.4L VIN 64 B5244S6 (2003)
The by-pass valve also functions as a non-return valve, ensuring that the fuel pressure in the system is maintained when the engine is switched off.
There is high pressure before the engine is started. This high pressure means that the valve in the by-pass valve opens and the system is "flushed".
For safety reasons, the engine control module (ECM) shuts off the fuel pump (FP) if the supplemental restraint system module (SRS) detects a collision.