Electronic Throttle Control Module: Description and Operation

1999 Volkswagen Passat Syncro Sedan (3B2) V6-2.8L (AHA)SECTION Description and Operation



Throttle Valve Control Module

Function
Idle speed stabilization is integrated in the throttle valve control module -J338-. In the housing opposite the throttle valve are Throttle Position (TP) sensor -G69-, Closed Throttle Position (CTP) switch -F60-, throttle drive -G186- and angle sensor -1- for throttle drive -G187-.

The individual components cannot be replaced or mechanically adjusted. All adjustments are accomplished by the VAG1551 Scan Tool (ST) using the "Basic Setting" function 04.

If the complete throttle valve control module is without power (i.e. disconnected), the throttle valve assumes a mechanical closed throttle position that results in an increased idle speed of 1200-1300 RPM (with engine at operating temperature).

If only the Throttle Position (TP) actuator -V60- is without power, the throttle valve also assumes a mechanical closed throttle position (limp-home position), but because the signal from the CTP switch -F60- can still be recognized, a nearly "normal" idle speed of approx. 900 RPM is maintained with a corresponding reduction of the ignition timing advance.

If the Engine Control Module (ECM) recognizes a malfunction in the angle sensor -1- for throttle drive -G187-, it switches the power off for throttle drive -G186-, and the throttle valve again assumes the mechanical closed throttle position (limp-home position).
RENDER: 1.0x

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