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.
• Voltage for the Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80) is supplied via the Motronic Engine Control Module (ECM) Power Supply Relay (J271).
Test procedure
- Perform a preliminary check to verify the customers complaint. Refer to => [ General Diagnosis ] General Diagnosis.
Start diagnosis
- Disconnect the Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80) electrical harness connector - 1 -.
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.
- 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 Motronic Engine Control Module (ECM) Power Supply Relay (J271) terminal 2/87 for an open circuit according to wiring diagram.
If the specified value 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 specified value was obtained:
Check Ground (GND) activation
- Using a Multimeter, check the Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80) electrical harness connector to Battery positive (+) for voltage.
- Operate the starter briefly.
Specified value: battery voltage.
- Switch the ignition off.
If the specified value was not obtained:
If the manufacturers test box is being used. Perform the following step.
- Install the test box. Refer to repair information.
If the manufacturers test box is not being used. Perform the following step.
- Remove the Motronic Engine Control Module (ECM) (J220). Refer to => [ Motronic Engine Control Module, Replacing ] Motronic Engine Control Module, Replacing.
- Using a Multimeter, check the Evaporative Emission (EVAP) Canister Purge Regulator Valve (N80) electrical connector terminal 2 to the Motronic Engine Control Module (ECM) (J220) electrical connector T121 terminal 64 for an open circuit.
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 Motronic Engine Control Module (ECM) (J220). Refer to => [ Motronic Engine Control Module, Replacing ] Motronic Engine Control Module, Replacing.
Final procedures
After repair work, the following work steps must be performed in the mentioned sequence:
1. Check the DTC memory.
2. If necessary, erase the DTC memory.
3. If the DTC memory was erased, generate readiness code.
- End diagnosis and switch the ignition off.