Activated charcoal filter shutoff valve | ||
1 | Fault code ( Readout on generic scan tool) | P2025 Activated charcoal filter shutoff valve, voltage supply (P0446) P2012 Activated charcoal filter shutoff valve, plausibility (P0446) |
2 | Fault storage Actuation CHECK ENGINE (MIL) malfunction indicator lamp | after expiry of test duration and fault following two successive driving cycles with faults |
3 | Checking frequency | Continuous |
4 | Checked signal or status | Voltage and current for activated charcoal canister shutoff valve |
5 | Fault setting conditions Limit values for voltage supply Short circuit to ground Short circuit to +12 V Open circuit in wiring Checking duration Plausibility |
Voltage lower than 4 volts Current higher than 4.2 amps No voltage on activated charcoal filter shutoff valve Approx. 4 to 8 V on under no load output of the ME control unit approx. 1 seconds If an excessively high vacuum is measured in the fuel tank by the fuel tank pressure sensor before beginning the leak test on the purge system then a blocked activated charcoal filter shutoff valve will be suspected and fault P2012 will be issued. |
6 | | Actuation of the activated charcoal canister shutoff valve is checked concerning a cable open-circuit and short-circuit (to ground or battery voltage). A short circuit to ground and a line discontinuity 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. The output stage is immediately no longer activated when a fault arises. |