Cooling System Draining And Filling (HV Battery And eMotor)
Mobile Repair Possible: No
Special Tools Required:
Hose Spring Clamp Removal Tool - 51012018 (or equivalent)
Vacuum and Fill Machine - 81392152473
In some Service Instructions, the coolant hoses are shown with a ring pull (1).
This ring pull (1) is only present on a new hose and must be removed after the coolant hose has been installed.
The coolant hoses installed in the vehicle have only spring band clamps (2).
Overview:
Failure to follow specified procedures may result in death or serious injury from electric shock when working on or near high-voltage components.
- Only authorised and appropriately trained persons may carry out work on high-voltage vehicles and components.
- Perform High Voltage isolation procedure prior to commencing work
- Ensure appropriate Personal Protective Equipment is worn until the system is verified safe
Failure to follow specified procedures may result in severe injuries due to burns or scalds.
- Do not commence work until components/liquids have sufficiently cooled down.
- Always use personal protective equipment (PPE).
Contamination or moisture entering the cooling system can lead to malfunction or functional failure.
- The vehicle cooling system and any removed components should be capped/sealed during work to prevent contamination entry
Draining Procedure:
To drain the HV battery, the inlet and outlet hoses must also be removed.
- Remove the air inlet grille. Refer to AIR INLET GRILLE PANEL AND EXTENSION REMOVAL AND INSTALLATION/REPLACEMENT
- Disconnect the 12V battery negative terminal. Refer to 12V BATTERY NEGATIVE CABLE DISCONNECTION/CONNECTION
- Remove front bumper fascia. Refer to FRONT BUMPER FASCIA SKID PLATE REMOVAL AND INSTALLATION/REPLACEMENT
- Cover the cooling system expansion tank cap (1) with a rag or cloth and open carefully by hand.
If there is a hissing sound, do not open the cover further until the hissing stops.
- Remove the cooling system expansion tank cap (1) by unscrewing it.
- Using Spring Band Hose Clamp Pliers to disconnect the eMotor Waterpump Inlet Hose (2) and Chiller Inlet Hose (3).
Pull down so that the maximum amount of coolant is drained and both coolant radiators are emptied.
NOTE: Environmental Risk- Collect and dispose of leaking liquids.
- Observe country-specific disposal regulations.
Filling Procedure:
Installation note: Use the spring band hose clamp pliers to push the hose on. If replacing with a new hose, you will remove the ring pull (1) to release the clamp. Refer to Figure Make sure that the spring band clamp is aligned inside the marking on the hose . Refer to HOSE CLAMP REMOVAL AND INSTALLATION/REPLACEMENT GUIDELINES - SPRING TYPE
- Reconnect the coolant hoses (1) and (2).
Installation note: Check the coolant hoses before filling the coolant circuit with the Vac-N-Fill machine
- There must be sufficiently premixed coolant in the filling unit container, 1-2 litres more than the vehicle filling capacity.
- Use only recommended coolant. Refer to APPROXIMATE FLUID CAPACITIES AND SPECIFICATION
- Position the filling unit container at the same height as the coolant expansion tank.
- Compressed-air connection with 6 bar pressure present.
- Connect filling unit (1) to coolant expansion tank using suitable adapter (2) from Adaptor Kit 83300494417.
Shutoff valves (A) and (B) must be closed.
- Connect venturi nozzle (1) to filling unit (2)
- Connect compressed air (1) and open shutoff valve (B).
The venturi nozzle produces a flow noise.
- Then open shutoff valve (A) until the filling hose (1) is free of bubbles.
Close shutoff valve (A) again.
The filling hose (1) is vented in this way.
- Shutoff valve (B) will remain open.
Generate vacuum in cooling cycle for approx. 1 minute.
The end vacuum is reached at a vacuum of - 0.7 to - 0.95 bar.
Green scale on the vacuum meter.
The coolant hoses contract during vacuum build-up.
Then close shutoff valve (B) again.
- Both shutoff valves (A) and (B) must be closed. Then seal Venturi nozzle (1).
- The cooling system must hold the vacuum for 30 seconds.
If the needle in the vacuum meter falls, this indicates a leak in the cooling system. If the vacuum remains constant, proceed with filling.
In the event of leaks, check cooling system for leaks.
- There must be sufficiently premixed coolant in the filling unit container, 1 - 2 litres more than the vehicle filling capacity.
Position the filling unit container at the same height as the coolant expansion tank.
Shut-off valve (B) remains closed during the filling process.
To fill the cooling system, open shutoff valve (A) to filling unit container.
Coolant is now added.
- The filling procedure is finished when the needle in the vacuum meter is at 0 bar or no longer falls.
If necessary, reduce remaining vacuum. Open shutoff valve (B) to do so.
Remove Vac-N-Fill unit with adapter from expansion tank.
- Adjust coolant level to MAX fill line (1). Re-fit Expansion Tank Cap (2).
- Reconnect the 12V Battery negative terminal. Refer to 12V BATTERY NEGATIVE CABLE DISCONNECTION/CONNECTION
- Install Front Bumper Fascia. Refer to FRONT BUMPER FASCIA SKID PLATE REPLACEMENT
- Diagnostics, Programming and Setup. Refer to DIAGNOSTICS, PROGRAMMING AND SETUP USING IDS IN SERVICE
- Using IDS, run the Water Pumps to bleed air out of cooling system.
- Stop Water Pumps, open the bleed screw (1) at the Heater outlet Hose to bleed any air trapped in the cooling system.
Once coolant starts to exit, close the bleed screw.
- Check coolant level in Expansion Tank. If required, add coolant to MAX fill line (1), then re-fit expansion tank cap.
- Install the air inlet grille. Refer to AIR INLET GRILLE PANEL AND EXTENSION REMOVAL AND INSTALLATION/REPLACEMENT