Canister Purge Control Valve: Testing and Inspection

Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80-, Checking







Special tools and equipment
- VAG1526A
- VAG1527B
- VAG1594A
- VAG1598/31
- VAS5051 with VAG5051/1
- or
- VAG1551 with VAG1551/3A

Checking for proper seal
When there is no current, the Evaporative Emission (EVAP) canister purge regulator valve -N80- is closed.

- Disconnect hoses from EVAP valve; harness connector remains connected.
- Attach assisting hose to one connection of
- Connect VAS5051 tester or VAG1551 scan tool and select control module for engine electronics using "address word". Ignition must remain switched on. Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks" Testing and Inspection
- Initiate output DTM and activate Evaporative Emission (EVAP) canister purge regulator valve -N80-. Refer to "Scan Tool Testing/Output Diagnostic Test Mode (DTM) (Function 03)" Testing and Inspection

Indicated on display(or, indicated: tank ventilation valve -N80-)


Output Diagnostic Test Mode (DTM) ->
EVAP canister purge regulator valve -N80-


- Valve must click...
- . . .and must open and close (can be tested by blowing into assisting hose).

If valve does not click:
- Check internal resistance of EVAP valve.

If valve does not open or close properly:
- Replace Evaporative Emission (EVAP) canister purge regulator valve -N80-.

Checking internal resistance
- Disconnect connector at EVAP valve.







- Connect multimeter at valve for resistance measurement.
- Specification: 22 to 30 Ohms

If specified value is not obtained:
- Replace Evaporative Emission (EVAP) canister purge regulator valve -N80-.

If specified value is obtained:
- Check voltage supply.

Checking voltage supply

Test requirements:
- Fuse for the EVAP valve OK.
- Fuel Pump (FP) relay OK; Testing and Inspection


NOTE: Voltage is supplied to the EVAP valve via the Fuel Pump (FP) relay.


- Disconnect connector at EVAP valve.







- Connect VAG1527B voltage tester as follows:

Harness connector Measure to
Terminal
1 Engine Ground (GND)

- Operate starter briefly (engine can also start).
- LED must light up.

If LED does not light up:
- Check wire connection from terminal 1 of connector to Fuel Pump (FP) relay via fuse for open circuit:
- Repair open circuit if necessary.

If LED lights up:
- Checking activation.

Checking activation







- Connect VAG1527B voltage tester to connector terminals 1 (B+) and 2.
- Initiate output DTM and activate Evaporative Emission (EVAP) canister purge regulator valve -N80-. Refer to "Scan Tool Testing/Output Diagnostic Test Mode (DTM) (Function 03)" Testing and Inspection
- LED must blink.

If LED does not blink or if it remains constantly lit:
- Connect VAG1598/31 test box at wiring harness to Engine Control Module (ECM), do not connect ECM. Refer to "Scan Tool Testing/Wiring and Component Testing Using VAG1598/31 Test Box", Testing and Inspection







- Check following wire connection for open circuit and short circuit to Ground (GND) and B+:

Harness connector VAG1598/31 test box
Terminal Socket
2 64

- Repair open circuit or short circuit if necessary.

If wire connection is OK:
- Replace Engine Control Module (ECM).