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EVAP Canister Purge Regulator Valve, Checking






EVAP Canister Purge Regulator Valve, Checking

Special tools, testers and auxiliary items required

• Multimeter

• wiring diagram

Test requirements

• The fuse for the Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80) OK.

• The ignition switched off.

• Voltage for the Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80) is supplied by the Engine Component Power Supply Relay (J757).

Test procedure

- Perform a preliminary check to verify the customers complaint. Refer to => [ Readiness Code ] Readiness Code.

Start diagnosis

- Disconnect the electrical harness connector from the Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80).

- Check the electrical harness connector for damage, corrosion, lose or broken terminals.

Checking internal resistance

- Using the Multimeter, check the resistance between the terminals of the Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80).

Specified value: 22.0 to 30.0 ohms.

If the specified value is not obtained:

- Replace the Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80).

Checking voltage supply

If the specification is obtained:

- Using the Multimeter, check the electrical harness connector terminal 1 to 2 for voltage.





- Operate the starter briefly.

Specified value: approx. battery voltage

If there is no voltage:

- Using the Multimeter, check the electrical harness connector terminal for voltage.





- Operate the starter briefly.

Specified value: approx. battery voltage

If there is no voltage again:

- Turn key off.

- Check the wiring connection from the electrical harness connector terminal 1 to the Leak Detection Pump (LDP) (-V144-) terminal 3 for an open circuit according to wiring diagram.

Specified value: Wire resistance max 1.5 ohms.

- If necessary, repair the wiring connection.

If the voltage supply is OK:

Check Ground (GND) activation

- Using the Multimeter , check the electrical harness connector for resistance.









Specified value: approx. < 10 ohms.

If the specified value is not obtained:

- Using a Multimeter , check the following wire connection for open circuit.









Specified value: Wire resistance max 1.5 ohms.

Specification: 0 ohms.

If the specification is not obtained:

- Check the wiring for a short circuit to Battery positive (+) or an open circuit.

- If necessary, repair the wiring connection.

- Erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory.

- Perform a road test to verify repair.

If the DTC does not return:

Repair complete, Generate readiness code. Refer to => [ Readiness Code ] Readiness Code.

- End diagnosis.

If the DTC does return and no malfunction is detected in the wiring and the voltage supply was OK:

- Replace the Motronic Engine Control Module (ECM) (J623). Refer to => [ Motronic Engine Control Module, Replacing ] Motronic Engine Control Module, Replacing.

Final procedures

After the repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to => [ Diagnostic Mode 03 - Read DTC Memory ] Diagnostic Mode 03 - Read DTC Memory.

2. If necessary, erase the DTC memory. Refer to => [ Diagnostic Mode 04 - Erase DTC Memory ] Diagnostic Mode 04 - Erase DTC Memory.

3. If the DTC memory was erased, generate readiness code. Refer to => [ Readiness Code, Setting ] Readiness Code, Setting.

End of diagnosis.