Cooling System
Coolant Hose Connection Diagram
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.
Risk of injury from coolant fan starting by itself.
• The radiator fan can come on even when the ignition is turned off, for example, caused by the heat still in the engine compartment.
• Secure all hose connections with hose clamps appropriate for the model.
• 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 the charge air cooler.
• Brown = heating circuit.
1 Cooler for the Charge Air Cooling Circuit
• Change coolant after replacing
2 Radiator
• With ATF cooler
• Change coolant after replacing
3 Engine Coolant Temperature Sensor (G62)
4 Coolant Auxiliary Cooler
• Depending on country
• Change coolant after replacing
5 Non-Return Valve
• Arrow in flow direction
• In the coolant hose
6 Coolant Thermostat
7 Coolant Pump
8 Right Charge Air Cooler
• In the housing for the supercharger with charge air cooler
• Change coolant after replacing
9 Bleeder Screw
10 Cylinder Head Bank 1 (right)
• Change coolant after replacing
11 Pump Valve Unit
• For heating control
12 Heater Unit Heat Exchanger
• Change coolant after replacing
13 Restrictor
• In the coolant hose
14 Bleeder Hole
15 Cylinder Head Bank 2 (left)
• Change coolant after replacing
16 Bleeder Screw
17 Left Charge Air Cooler
• In the housing for the supercharger with charge air cooler
• Change coolant after replacing
18 Coolant Reservoir Cap
• Pressure relief valve, checking Component Tests and General Diagnostics
19 Coolant Reservoir
20 Engine Oil Cooler
21 After-Run Coolant Pump (V51)
• Depending on country
22 Non-Return Valve
• Arrow in flow direction
• In the coolant hose
23 Charge Air Coolant Pump (V188)
24 Bleeder Screw