Diagnostic Aids
WARNING: This page is about a different car, the 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, 2003 Ford Excursion, and 2003 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The Variable Geometry Turbo (VGT) actuator is a variable position valve that controls vane position in the turbine housing. The VGT is located on top of the turbocharger. The valve position is controlled by switching voltage source inside of the PCM.
The PCM will detect an open or short in the VGT control circuit after the KOEO test has run and set a DTC.