Exhaust Gas Recirculation Vacuum Regulator Solenoid Valve, Checking

Exhaust Gas Recirculation Vacuum Regulator Solenoid Valve, Checking

Special tools, testers and auxiliary items required

• Multimeter.

• Wiring diagram.

Test requirements

• Fuse (on fuse panel) (S234) OK.

• The ignition switched off.

• Voltage for the EGR Vacuum Regulator Solenoid Valve (N18) is supplied by the Power Supply Relay (terminal 30, B+) (J317).

Test procedure

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

Start diagnosis

- Disconnect the EGR Vacuum Regulator Solenoid Valve (N18) electrical harness connector.





Checking internal resistance

- Using a Multimeter, check the EGR Vacuum Regulator Solenoid Valve (N18) terminals 1 and 2 for resistance.

Specified value: 14 to 18 ohms.

If the specified value is not obtained:

- Replace the EGR Vacuum Regulator Solenoid Valve (N18).

If the specification is obtained:

Checking voltage

- Switch the ignition on.

- Using a Multimeter, check the EGR Potentiometer (G212) electrical harness connector terminal 1 to Ground (GND) for voltage.





Specified value: Battery (+).

If the specified value was not obtained:

- Check the EGR Potentiometer (G212) electrical harness connector terminal 1 to the Power Supply Relay (terminal 30, B+) (J317) socket 6/87 for an for an open circuit or a short circuit.

- Check the wiring connections for damage, corrosion, loose or broken terminals.

- If necessary, repair the faulty 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. Refer to => [ 68-Pin Test Box Adapter, VAG1598/19, Installing ] Diesel Direct Fuel Injection ECM, Checking.

If the manufacturers test box is not being used, perform the following step.

- Remove the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) (J248). Refer to => [ Diesel Direct Fuel Injection ECM, Replacing ] Diesel Direct Fuel Injection ECM, Checking.

- Using a Multimeter, check the EGR Vacuum Regulator Solenoid Valve (N18)/EGR Potentiometer (G212) electrical harness connector terminal to the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) (J248) electrical harness connector T60 terminal for resistance.









Specified value: 1.5 ohms Max.

If the specification was not obtained:

- Check the wiring for a short circuit to each other, Battery (+), and Ground (GND).

- If necessary, repair the faulty wiring connection.

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

If no malfunction is detected in the wiring:

- 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 not OK:

- Replace the Diesel Direct Fuel Injection (DFI) Engine Control Module (ECM) (J248). Refer to => [ Diesel Direct Fuel Injection ECM, Replacing ] Diesel Direct Fuel Injection ECM, Checking.

- Assembly is performed in the reverse of the removal.

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 ] Readiness Code.