Cooling System: Diagrams

2012 Audi A8 Quattro Sedan (4H2) V8-4.2L (CDRA)SECTION Diagrams





Coolant Hose Connection Diagrams

Risk of scalding due to hot steam and hot coolant.

The coolant system is under pressure when the engine is warm.

Cover the coolant reservoir cap with a cloth and then open it slowly to release the pressure in the system.

Secure all hose connections with hose clamps appropriate for the model, refer to the electronic parts catalog ETKA.

The arrows on the coolant pipes and ends of coolant hoses must align.

Blue = large coolant circuit.

Red = small coolant circuit.

Orange = coolant circuit for ATF cooling.

Brown = heating circuit.






1 Radiator

Change coolant after replacing

2 Engine Temperature Control Temperature Sensor (G694)

3 Generator

4 Engine Oil Cooler

Change coolant after replacing

5 Cylinder Head

Cylinder bank 1 (right)

Change coolant after replacing

6 Coolant Temperature Sensor (G62)

7 Coolant Recirculation Pump (V50)

8 Bleeder Screw

9 Coolant Switch-Off Valve (N82)

10 Front Heater Unit Heat Exchanger

Change coolant after replacing

11 Rear Heater Unit Heat Exchanger

Change coolant after replacing

12 Transmission Coolant Valve (N488)

13 Crankcase Ventilation

14 ATF Cooler

15 Non-Return Valve

16 Cap

Pressure relief valve, checking => [ Pressure Relief Valve
in Cap, Checking ] Testing and Inspection

17 Coolant Reservoir

18 Cylinder Head Coolant Valve (N489)

19 Cylinder Head

Cylinder bank 2 (left)

Change Coolant after replacing

20 Coolant Pump

21 Map Controlled Engine Cooling Thermostat (F265)

22 After-Run Coolant Pump (V51)

23 Transmission Fluid Cooling Valve (N509)

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.