With Manufacturer's Scan Tool

EVAP canister purge regulator valve -N80-, checking

In a no-current situation the solenoid valve is closed.

Special tools and equipment





^ V.A.G 1551 Scan Tool (or vehicle system tester V.A.G 1552) with cable VAG 1551/3

Note: All functions which could previously be performed with V.A.G. 1551/1552 can also be performed with the new tester VAS 5051.





Test conditions
^ The fuses must be OK.
^ The battery voltage must be at least 11.5 V.
^ All electrical consumers, e.g. lights and rear window heating must be switched off.
^ If the vehicle is equipped with air conditioning, this must be switched off.
^ Selector lever must be in position "P" or "N" on models with an automatic transmission.
^ Fuel pump relay -J17- must be OK, checking:
Refer to Electrical Wiring Diagrams, Troubleshooting & Component Locations
^ No DTC's may be stored in DTC memory:
Refer to Powertrain Management

Checking activation
- Check activation of EVAP canister purge regulator valve -N80- via output Diagnostic Test Mode (DTM):
Refer to Powertrain Management
If activation is OK:
- Perform functional check.

Functional check
Test conditions
^ Coolant temperature must be at least 85°C,Refer to display group 1, display zone 2.

Test sequence
- Connect V.A.G 1551 Scan Tool (or V.A.G 1552). Start engine and select "Address word" 01 of engine control module.
Refer to Powertrain Management





Indicated on display
- Press keys O and 4 for function "Initiate basic setting" and confirm entry with Q key.





Indicated on display
- Press keys 0, 0 and 1 for"Display group number 1" and confirm entry with Q key.





Indicated on display (1...4 = display zones)

Only continue with the test when
^ The coolant temperature is above 85°C -Display zone 2

- Change to display group 70 as follows:
- Press C key.





Indicated on display
- Press keys 0, 7 and 0 for "Display group number 70" and confirm entry with Q key.

Note: The engine must not be loaded during this diagnosis, if this occurs the diagnosis will be interrupted and will not start again until the engine is revved-up.





Indicated on display (1 4 = display zones)
If the diagnosis is initiated by the engine control module the display in display zone 4 jumps from "Test OFF" to "Test ON".

Note: This process can take approximately 30 seconds.

- Leave engine running at idling speed until display zone 4 displays specification TBV OK.

Note: TB V stands for tank breather valve (EVAP canister purge regulator valve -N80t.

If "TBV OK" appears in display zone 4:
- Press (arrow) key.
- Press keys O and 6 for function "End output" and confirm entry with Q key.
- Switch ignition off.

If "TBV n. OK" appears in display zone 4:
- Press (arrow) key.
- Check DTC memory:
Refer to Powertrain Management
- Read readiness code

- Generate readiness code again if DTC memory has been erased or engine control module separated from permanent positive supply.
Refer to Powertrain Management1

If no DTC is stored in DTC memory:
- Press keys O and 6 for function "End output" and confirm entry with Q key.
- Switch ignition off.
- Check breather lines to EVAP canister (maybe kinked).
- Check EVAP system for leaks, Refer to Evaporative Emission System, Testing and Inspection