Divert air switchover valve, ME-SFI fault code description - AD07.61-P-4001-01M
| Divert air switchover valve (Y101) | ||
|---|---|---|
| 1 | Fault code (Fault code according to OBD) |
P2027 (-) |
| 2 | Fault storage | After expiry of test duration and fault |
| Actuation of engine diagnosis indicator lamp (EURO4) or CHECK ENGINE (MIL) |
no activation | |
| 3 | Checking frequency | Continuous |
| 4 | Checked signal or status | Current/voltage test on divert air switchover valve |
| 5 | Fault setting conditions | |
| Short circuit to ground | Voltage lower than 4 volts | |
| Short circuit to positive | Current higher than 4.2 A | |
| Open circuit in wiring | No voltage on divert air switchover valve ca. 4 to 8 V on the under no load output of the ME control unit | |
| 6 | Check prerequisites | Battery voltage between 8 and 17 V |
| 7 | Actuation is checked for a line interruption and short-circuit (to ground or battery voltage). A short circuit to ground and a cable breakage will be recognized when the output stages are locked, while a short circuit to the battery voltage is recognized when the output stages are conducting. In case of a fault the output stage will no longer be actuated immediately and the deceleration air valves remain closed. This can lead to charging noises (a short howling) when changing over from high load to overrun mode. If one (or both) deceleration air valves remain open then the maximum boost pressure will no longer be reached. If the divert air switchover valve is actuated to test it one hears the deceleration air valves on the turbochargers switch just once or twice. The vacuum reservoir is empty after that and new vacuum must be built up through short operation in idle. In case of a fault check the hose lines for leaks. |