Connection Diagram - Coolant Hoses, AUDI A4/A5 And Q5 Without High-Voltage System, Without Parking/Auxiliary Heater

• Blue = large coolant circuit.
• Red = small coolant circuit.
• Brown = heating circuit.
• Green = coolant circuit for the transmission.
• Arrows = coolant flow direction.

Fig 1: Connection Diagram - Coolant Hoses, Audi A4/A5/Q5 Without Parking/Auxiliary Heater

Courtesy of AUDI OF AMERICA, LLC

1. Radiator
2. Cylinder Block
3. Check Valve
4. Turbocharger
5. Check Valve
6. Exhaust Manifold
7. Cylinder Head
8. Engine Coolant Temperature Sensor -G62-
9. Restrictor
10. Heater Core for the Heater
11. Coolant Recirculation Pump -V50-
12. Coolant Pump
13. Coolant Thermostat
    • For transmission coolant circuit
    • For version with dual clutch transmission
14. ATF Cooler
    • For version with dual clutch transmission
15. After-Run Coolant Pump -V51-
    • For version with dual clutch transmission
16. Check Valve
17. Restrictor
18. Cap
    • Check the pressure relief valve. Refer to COOLING SYSTEM, CHECKING FOR LEAKS .
19. Coolant Expansion Tank
20. Check Valve
21. Engine Coolant Temperature Sensor on Radiator Outlet -G83-
22. Engine Temperature Control Actuator -N493-
23. Engine Oil Cooler