Canister Purge Control Valve: Testing and Inspection

Evaporative Emissions (EVAP) Canister Purge Regulator Valve, Electrical Testing

- Disconnect harness connector from EVAP canister purge regulator valve -N80-.






- Connect multimeter US 1119 (Fluke 83 or equivalent) and measure resistance across valve terminals.
Specified value: 20 - 35 ohms

If resistance is not OK:
- Replace EVAP canister purge regulator valve.
- Check readiness code. If DTC memory has been erased, generate new readiness code.

Checking voltage supply
- Fuse for EVAP canister purge regulator valve -N80- OK (located in E-box in plenum)

- Disconnect harness connector from EVAP canister purge regulator valve -N80-.






- Connect VAG1527B LED voltage tester between connector terminal 1 and Ground.
- Switch ignition on.
LED must light up

If LED does not light:
- Check wiring between connector terminal 1 and fuse for EVAP canister purge regulator valve -N80- (E-box in plenum).

If wiring is OK:
- Check Motronic ECM power supply relay.

Checking valve actuation






- Connect VAG1527B LED voltage tester between harness connector terminals 1 (B+) and 2.
- Initiate output Diagnostic Test Mode (DTM) and check actuation of EVAP canister purge regulator valve -N80-.
LED must flash

If LED does not light, or lights continuously:
- Connect VAG1598/19 test box to Engine Control Module (ECM) harness connector.






- Check wiring between EVAP canister purge regulator valve connector terminal 2 and ECM/test box socket A8, and repair as necessary.

If EVAP components and wiring are OK:
- Check EVAP hoses and connections for leaks or blockage.

If EVAP hoses and lines are OK, and properly connected:
- Replace Engine Control Module (ECM).
- Generate readiness code.