Operation CHARM: Car repair manuals for everyone.

Variable Induction Control Valve: Testing and Inspection

ELECTRICAL CHECK
- Disconnect harness connector on intake manifold change-over valve.

Intake Manifold Change-over Valve Test:




- Switch multimeter (Fluke 83 or equivalent) to measure resistance and connect between terminals on valve.

Specified Value: 25-35 ohms

If specified value is not obtained:
- Replace intake manifold change-over valve.

CHECKING BATTERY POSITIVE VOLTAGE (B+) SUPPLY
- Disconnect harness connector on intake manifold change-over valve.

2-Pin Connector:




- Connect VAG 1527B voltage tester or equivalent between harness connector terminal 1 (positive) and Ground (GND) using adapter from VW 1594 connector test kit.
- Use On-Board Diagnostics (OBD) Output Diagnostic Test Mode (DTM) to activate fuel pump relay -J17-.

LED must light up.

If LED does not light up:
- Check fuse for intake manifold change-over valve.
- Check wiring for continuity between valve harness connector terminal 1 and circuit breaker using wiring diagram.

Specified Reading: 1.0 ohms.

- Check fuel pump relay and activation.

CHECKING INTAKE MANIFOLD CHANGE-OVER VALVE ACTIVATION
- Connect VAG 1527B voltage tester or equivalent across terminals 1 and 2 of intake manifold change-over valve connector using adapter from VW 1594 connector test kit.
- Use On-Board Diagnostics (OBD) Output Diagnostic Test Mode (DTM) to activate intake manifold change-over valve.

LED must blink when intake manifold change-over valve is activated.

If LED does not blink or lights up continuously:
- Connect VAG 1598/19 test box to ECM wiring harness. Refer to Computer and Control Systems, System Diagnosis, VAG 1598 Pin Out Box Connecting.

If LED lights up continuously:
- Check wiring for short circuit to GND between intake manifold change-over valve connector terminal 2 and test box socket B4.

If LED does not flash:
- Check wiring for continuity between intake manifold change-over valve connector terminal 2 and test box socket B4.

Specified Reading: maximum 1.0 ohm




- If necessary, eliminate short circuit to GND or wiring break between intake manifold change-over valve connector terminal 2 and terminal 4 of ECM connector B.

If there is no wiring break or short circuit:
- Replace ECM.