P00AF/000175

000175/P00AF - Actuator Module for Turbocharger 1: Stuck

Possible Symptoms

• Malfunction Indicator Light (MIL) ON
• Glow Plug light flashing
• Reduced engine performance

Possible Causes

• Defective N75
• N75 connector plugged into the wrong 2 wire component. Check wiring diagram to confirm
• Vacuum leak or low vacuum
• VNT sticking or seized
• G581 sensor

Possible Solutions

• Verify N75 is working to design, use Output Testing
• Verify the N75 connector plugged into N75 per the factory level wiring diagram rather than any other component that may not set a fault code such as N79 (Positive Crankcase Ventilation (PCV) heating element)
• Verify vacuum lines are good, check engine vacuum at idle
• Test VNT and G581, apply vacuum to VNT and watch MVB 120.4
  • Engine off, no vacuum 120.4 should read about 3.5V
  • Engine Off, apply 17 Inches of mercury, 120.4 should drop to about .7V
  • Engine at idle, 120.4 should read about 7.V
  • If 120.4 voltage doesn't alter, VNT may be seized or G581 failed

Special Notes

• On some TDI engines, the Vacuum Diaphragm/G581 unit can be purchased as a separate part from dealer.
• 2.0L CR TDI owners may find the following threads helpful:
  • http://forums.ross-tech.com/showthread.php?404-009571-Turbocharger-Boost-Control-Position-Sensor-Circuit-P2563
  • http://forums.ross-tech.com/showthread.php?4891-2009-TDi-Having-issues-with-Turbo-seeking-some-advise
    • Post #10 includes a YouTube video link.