Connection Diagram - Coolant Hose, Vehicle With 2.9L Engine

• Blue = large coolant circuit.
• Red = small coolant circuit.
• Pink = coolant circuit for charge air cooler.
• Orange = cylinder block coolant circuit
• Brown = heating circuit.
• Green = coolant circuit for the transmission.
• Arrows = coolant flow direction.

Fig 1: Coolant Hose Connection Diagram (Vehicle With 2.9L Engine)

Courtesy of AUDI OF AMERICA, LLC

1. Radiator
   • for transmission coolant circuit
2. Right Auxiliary Radiator
3. Engine Coolant Temperature Sensor on Radiator Outlet -G83-
4. Coolant Thermostat
   • For right auxiliary radiator
5. Map Controlled Engine Cooling Thermostat -F265-
6. Engine Coolant Temperature Sensor on Engine -G82-
7. Coolant Shut-Off Valve
   • Vacuum-controlled
8. Engine Temperature Control Sensor -G694-
9. Cylinder Head
   • Cylinder Bank 1 (Right)
10. Cylinder Block
11. Turbocharger
    • Cylinder Bank 1 (Right)
12. Check Valve
13. Restrictor
14. Bleed Hole
15. Heater Core for the Heater
16. Coolant Recirculation Pump -V50-
17. After-Run Coolant Pump -V51-
18. Cap
    • Checking the pressure relief valve. Refer to COOLING SYSTEM, CHECKING FOR LEAKS .
19. Coolant Expansion Tank
20. Check Valve
21. Coolant Thermostat
    • for transmission coolant circuit
22. Radiator
    • For gear oil
23. ATF Cooler
24. Turbocharger
    • Cylinder Bank 2 (Left):
25. Engine Oil Cooler
26. Cylinder Head
    • Cylinder Bank 2 (Left):
27. Engine Coolant Temperature Sensor -G62-
28. Cylinder Block
29. Check Valve
30. Restrictor
31. Restrictor
32. Coolant Pump
    • Activated by the Mechanical Coolant Pump Switch Valve -N649-
33. Check Valve
34. Charge Air Cooling Pump -V188-
35. Charge Air Cooler
36. Bleed Screw
37. Lower Front Auxiliary Radiator
38. Front Auxiliary Radiator
39. Radiator
40. Check Valve
41. Bleed Screw