Activating Intake Manifold change-over valve N156

Indicated on display

Output Diagnostic Test Mode ->
Intake Manifold change-over valve N156

The twin path intake manifold change-over valve must click until the next final control is activated by pressing the → button.

NOTE:

If there is sufficient vacuum the twin path Intake manifold change-over valve N156 activates the valve actuating element. The change-over valve is located below the intake manifold, on the right-side next to the secondary air injection valve. Checking Intake manifold change-over valve → Intake Manifold change-over valve N156 , checking .

If the valve does not click:

Fig 1: Intake Manifold Change-Over Valve N156

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Disconnect 2-pin harness connector from Intake manifold change-over valve N156 - arrow -.

Fig 2: Checking Voltage Of 2-Pin Connector Of Intake Manifold Change-Over Valve N156

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Using adapter cables from VW 1594 connect voltage tester VAG 1527B to disconnected harness connector. LED must flash (bright/darker).

If LED flashes:

Proceed with output DTM until completed.
Switch ignition off.
Replace Intake Manifold change-over valve N156.
Check DTC memory. If necessary, repair any malfunctions and erase DTC memory → Diagnostic Trouble Code (DTC) memory, checking and erasing (scan tool functions 02 and 05) .

Display readiness code → Readiness code (function 15), displaying . If DTC memory has been erased, the readiness code must be generated again → Readiness code (function 15), generating .

If LED does not flash:

Proceed with output DTM until completed.
Switch ignition off.
Remove wiper arms and plenum chamber cover. → 92 WINDSHIELD WIPER & WASHER SYSTEM

Fig 3: Identifying Test Box V.A.G 1598/31 Connected To Control Module Wiring Harness

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Connect Test box VAG 1598/31 to control module wiring harness. Engine control module is not connected by this action.

Fig 4: 2-Pin Electrical Harness Connector & Terminals

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Check wire between test box socket 104 and 2-pin harness connector terminal 4 on relay plate for open circuit using wiring diagram. Wire resistance: max. 1.5 Ω
Using wiring diagram, check wire between terminal 1 of relay plate and Fuel Pump (FP) relay J17 for open circuit. Wire resistance: max. 1.5 Ω

If no wiring malfunction is detected: