ME9 / P0446 00

Read the instructions below then start the fault diagnostic procedure.

Symptom: Fault indicator lamp (for further information see WIS Fault diagnosis, general)

P0446 00

Fault symptom

Fault indicator lamp (for further information see WIS Fault diagnosis, general)

On-board diagnosis

Type of diagnosis:

Once per driving cycle.

Enable criteria:

Battery voltage must be between 10 - 18 V.

Engine running.

Tank pressure lower than -0.8kPa.

Tightness diagnosis active (P0456).

Purge valve closed.

When these conditions are met, the valve opens. Afterwards, diagnostics checks if the tank pressure has risen to the desired level within a calibrated time period.

Fault criteria:

Tank pressure does not increase when the valve opens.

Dependent:

None

System reaction to a fault:

Fuel adaption is blocked and reset.

Purge blocked.

Diagnostic help

Diagnosis regards:

Blockage of fresh air intake via shut-off valve to evaporative emission canister or from the evaporative emission canister to the tank.

Functions in the diagnostic tool related to the fault:

Activation:

•	Canister Close Valve

(See also description of readings/activations in diagnostic tool)