Fuel Tank Breather, Checking
Fuel Tank Breather, Checking
Evaporative Emission (EVAP) canister purge regulator valve -N80-, checking
Special tools and equipment
- VAG 1526 A
- VAG 1527 B
- VAG 1594 A
- VAG 1598/31
- VAS 5051 with VAS 5051/1
Testing for leaks
When there is no electrical supply, solenoid valve remains closed.
- Disconnect hoses from EVAP canister purge regulator valve but leave electrical connector plugged in.
- Connect auxiliary hose to one connection of EVAP canister purge regulator valve.
- Connect testing and information system VAS 5051 and select vehicle system "01 - Engine electronics" in selection. Ignition must be switched on.
- Initiate final control diagnosis and activate EVAP canister purge regulator valve -N80-. Basic Setting (Function 04)
- The valve should click ...
... and should open and close (check by blowing into the auxiliary hose).
- Press <- button to end function "03 - Final Control Diagnosis" [also known as Output Diagnosis Test Mode (DTM)].
If valve does not open and close properly:
- Replace EVAP canister purge regulator valve -N80-.
If the injector does not click:
Checking internal resistance
- Disconnect connector on EVAP canister purge regulator valve.
- Connect multimeter to injector to measure resistance.
- Specified value: 22 to 30 Ohms
If specification is not obtained:
- Replace Evaporative Emission (EVAP) canister purge regulator valve -N80-.
If specified value is obtained:
Checking power supply
Test requirements
- Fuse for EVAP canister purge regulator valve OK.
- Fuel pump relay OK; Testing and Inspection
NOTE: The EVAP canister purge regulator valve receives its power supply via the fuel pump relay.
- Disconnect connector on EVAP canister purge regulator valve.
- Connect voltage tester VAG 1527 B as follows:
Connector Measure to
terminal
1 Engine ground
- Operate starter briefly (engine may start).
- LED should illuminate.
If the LED does not illuminate:
- Check wiring from terminal 1 on connector via fuse to fuel pump relay for an open circuit.
- Repair open circuit, if necessary.
If the LED illuminates:
Checking actuation
- Connect voltage tester VAG 1527 B to terminals 1 (positive) and 2 of connector.
- Initiate final control diagnosis and activate Evaporative Emission (EVAP) canister purge regulator valve -N80-. Basic Setting (Function 04)
- LED should flash.
If the LED lamp does not flash or if it illuminates continuously:
- Connect test box VAG1598/31 to wiring harness for engine control module; do not connect engine control module. Wiring and Component Testing Using VAG1598/31 Test Box
- Check for open circuit and short to positive or Ground in following wiring connection:
Connector Test box VAG 1598/31
terminal Socket
2 64
- Repair any open/short circuit as necessary.
If the wiring is OK:
- Replace engine control module.