P0444

P0444
EVAP Canister Purge Valve - Open Circuit.




P0445
EVAP Canister Purge Valve - Short Circuit to Plus/short Circuit to Ground.

Function:
The fuel vapors from the fuel tank must not escape into the open air. For this reason, the ventilation line of the fuel tank is routed to an evaporative emission filter that retains the fuel vapors. When driving, air is drawn in through the evaporative emission filter which picks up the accumulated fuel vapors and feeds them to the combustion process. The EVAP canister purge valve is installed between the evaporative emission (EVAP) canister and intake system. The flow direction through the valve is indicated by an arrow on the plastic housing.
The end stage that controls the EVAP canister purge valve is monitored.

Diagnosis Conditions:
A fault is detected and stored if the engine speed is over 80 1/min and if the battery voltage is between 7.5 Volt and 17 Volt.

Wiring Diagram:



Image Legend:
A. ECM relay
B. EVAP canister

Diagnostic Procedure:

P0444:

P0445 short circuit to B+:

P0445 short circuit to ground:

1. Check voltage supply for EVAP canister purge valve.
1. Remove connector at EVAP canister purge valve.
2. Connect voltmeter (positive) to EVAP canister purge valve connector pin 2 and ground.
3. Switch on ignition.

Display: Battery positive voltage.

2. Check EVAP canister purge valve.
1. Remove connector at EVAP canister purge valve.
2. Connect ohmmeter to EVAP canister purge valve pin 1 and pin 2.

Display: 26 ± 4 Ohms at 20°C.

3. Check control line for EVAP canister purge valve.
1. Remove connector at EVAP canister purge valve.
2. Connect special tool 9616 to wiring harness.
3. Connect ohmmeter to EVAP canister purge valve pin 1 and special tool 9616 pin 61.

Display: 0 - 5 ohms.

4. Check control line for EVAP canister purge valve for short circuit to B+.
1. Remove connector at EVAP canister purge valve.
2. Connect special tool 9616 to wiring harness.
3. Connect voltmeter (positive) to EVAP canister purge valve connector pin 1 and ground.
4. Switch on ignition.

Display: 0 Volt.

If battery positive voltage is displayed, check wiring harness for chafing and pinching damage.

5. Check control line for EVAP canister purge valve for short circuit to ground.
1. Remove connector at EVAP canister purge valve.
2. Connect special tool 9616 to wiring harness.
3. Connect ohmmeter to EVAP canister purge valve connector pin 1 and ground.

Display: Infinity Ohms.

If 0 to 5 Ohms is displayed, check wiring harness for chafing and pinching damage.