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 Evaporative Emission (EVAP) Canister Purge Regulator Valve N80 fuse OK.
- The ignition switched off.

NOTE: 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. General Diagnosis

Start diagnosis







- Disconnect the Evaporative Emission (EVAP) Canister Purge Regulator Valve N80 electrical harness connector - 2 -.

Checking internal resistance







- Using a Multimeter , check the resistance between terminals 1 and 2 of the Evaporative Emission (EVAP) Canister Purge Regulator Valve N80.

Specified value: 22,0 to 30,0 Ohms.

If the specified value was not obtained:
- Replace the Evaporative Emission (EVAP) Canister Purge Regulator Valve N80.

If the specification is obtained:

Checking voltage supply







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

Specified value: battery voltage.
If the specified value was not obtained:
- Using a Multimeter , check the electrical harness connector terminal 1 to Ground (GND) for voltage.

Evaporative Emission (EVAP) Measure to
Canister Purge Regulator
Valve N80 Electrical Harness
connector Terminal
1 Engine Ground (GND)

- Operate the starter briefly.

Specified value: battery voltage.

If the specified value was not obtained:
- Check the wiring connection from the Evaporative Emission (EVAP) Canister Purge Regulator Valve N80 electrical harness connector terminal 1 to the Engine Component Power Supply Relay J757 terminal 2/87 for an open circuit or short to ground (GND).
- Check the electrical harness connector for damage, corrosion, lose or broken terminals.
- If necessary, repair the wiring connection.

If the specified value was obtained:

Checking wiring

If the manufacturers test box is being used. Perform the following step.
- Install the test box.

If the manufacturers test box is not being used. Perform the following step.
- Remove the Motronic Engine Control Module (ECM) J623.







- Using a Multimeter , check the Evaporative Emission (EVAP) Canister Purge Regulator Valve N80 electrical connector terminal 2 to the Engine Control Module (ECM) J623 electrical connector T60 terminal 5 for an open circuit.

Evaporative Emission (EVAP) Motronic Engine Control Module
Canister Purge Regulator Valve (ECM) J623 electrical connector
N80 Electrical harness T60 terminal or test box socket
connector terminal
2 5

Specified value: 1.5 Ohms

If the specification was not obtained:
- Check the wiring for a short circuit to Battery positive (+) or an open circuit.
- Check the electrical harness connector for damage, corrosion, lose or broken terminals.
- If necessary, repair the wiring connection.

If the specification was obtained:
- Replace the Engine Control Module (ECM) J623.

Final procedures
After repair work, the following work steps must be performed in the mentioned sequence:
1. Check the DTC memory. Diagnostic Mode 03 - Read DTC Memory
2. If necessary, erase the DTC memory. Diagnostic Mode 04 - Erase DTC Memory
3. If the DTC memory was erased, generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

- End diagnosis and switch the ignition off.