P00AF/000175
From Ross-Tech Wiki
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
- 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 this thread helpful: