With Manufacturer's Scan Tool
Evaporative Emissions (EVAP) canister purge regulator valve -N80-, checking
WARNING!
Whenever carrying out work on the fuel supply and/or fuel injection systems, read and carefully follow the Cautions, Warnings, and rules of cleanliness.
Required special tools and test equipment
- VAG 1551 or VAG 1552 Scan Tool (ST) with VAG 1551/3 adapter cable
Test conditions
- Engine coolant temperature at least 800° C (176° F)
Function check
- Connect VAG 1551 or VAG 1552 scan tool and press buttons -0- and -1- to insert "Engine Electronics" address word 01 (with engine running at idle).[1][2]Scan Tool Connecting and Initial Checks
Indicated on display
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -8- to select "Read Measuring Value Block" function 08, and press -Q- button to confirm input.
Indicated on display
Read Measuring Value Block HELP
Input display group number XXX
- Press buttons -0-, -7- and -0- to input display group number 70 (070), and press -Q- button to confirm input.
Indicated on display (1-4 = display fields)
Read Measuring Value Block 70 ->
1 2 3 4
- Press button -4- to select "Basic Setting" function 04 (diagnosis for EVAP canister purge regulator valve -N80- is initiated).
NOTE: During this diagnosis there should not be any load placed on the engine, otherwise the diagnosis is interrupted and must be started again.
Indicated on display (1-4 display fields)
System in Basic Setting 70 ->
1 2 3 4
If the diagnosis is initiated by the ECM, the display in display field 4 changes from "Test OFF" to "Test ON".
- Continue to run engine at idle until "EVAP OK" is indicated in display field 4.
NOTE: If the display changes from "Test ON" to "Test OFF" during the test, accelerate with a brief burst to repeat the test.
Display Group 70:
If "EVAP n.OK" is indicated in display field 4:
- Check for blockage or leaks.
If "EVAP OK" is indicated in display field 4:
- Press -> button.
Indicated on display
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -6- to select "End Output" function 06, and press -Q- button to confirm input.
Checking for blockage and leaks
The EVAP canister purge regulator valve is closed when power is off.
- Remove EVAP canister purge regulator valve -N80- (component location).
- Connect removed valve to harness connector.
- Start output Diagnostic Test Mode (DTM) and select -N80-.Output Diagnostic Test Mode (DTM) (Function 03)
- Blow into long connection during output DTM, and check whether valve opens and closes properly. Replace valve if necessary.
If valve -N80- does not open and close as specified:
- Replace -N80-.
If valve -N80- is OK:
- Check all hose connections between tank and valve for blockage or leaks.
EVAP canister purge regulator valve -N80- electrical test
- Disconnect harness connector from EVAP canister purge regulator valve.
- Connect multimeter US 1119 (Fluke 83 or equivalent) and check resistance across valve terminals.
Specified value: 22-30 Ohms
If resistance is NOT OK:
- Replace EVAP canister purge regulator valve.
Checking EVAP canister purge regulator valve voltage supply
Test conditions
- Fuse for EVAP canister purge regulator valve OK
- Disconnect harness connector from EVAP canister purge regulator valve.
- Connect VAG 1527B LED voltage tester between connector terminal 1 (B+) and engine Ground.
- Operate starter motor.
Specified value: LED must light up
If LED test light does not light:
- Check wiring for open circuit between connector terminal 1 and fuse, according to wiring diagram; repair if necessary.
Specified value: 1.0 Ohms max.
If wiring is OK:
- Check fuel pump relay. Refer to Testing and Inspection
Checking signal to EVAP canister purge regulator valve
- Connect VAG 1527B LED voltage tester between connector terminals 1 (B+) and 2.
- Start output Diagnostic Test Mode (DTM) for EVAP canister purge regulator valve - N80-.Output Diagnostic Test Mode (DTM) (Function 03)
LED must blink
If LED test light does not blink, or stays on:
- Connect VAG 1598/22 test box to ECM harness connector.Connecting VAG 1598/22 Test Box
If LED test light does not blink:
- Check wiring between connector terminal 2 and Motronic ECM terminal 15 for open circuit or short circuit to B+.
If LED test light stays on:
- Check wiring between connector terminal 2 and Motronic ECM terminal 15 for short circuit to Ground.
If wiring is OK:
- Replace Motronic ECM -J220-
- Carry out adaptation of throttle valve control module to ECM .
- Check readiness code.If Diagnostic Trouble Code (DTC) memory has been erased, or ECM was disconnected, generate new readiness code.
Readiness Code Reading
Readiness Code, Generating