Volkswagen 1.9-Liter TDI Owner's Manual page 52

Engine Management
J317
S
N239
48
J248
SSP209/070
Effects of failure
If the Change-Over Valve for Intake
Manifold Flap N239 fails, the intake
manifold flap stays open.
The tendency of the engine to shudder
when switched off will increase.
Electrical circuit
J217 Transmission Control Module
J248 Diesel Direct Fuel Injection Engine
Control Module
N239 Change-Over Valve for Intake
Manifold Flap
S Fuse