20–04 Hybrid Electric System
Coolant Changing
1.
Disconnect the 12-volt vehicle batteries to isolate
the high voltage power source.
2.
Drain the hybrid radiator, as follows.
2.1
Place a large container under the hybrid
radiator.
2.2
Remove the cap from the coolant reser-
voir.
2.3
If equipped with a petcock, open it at the
bottom of the hybrid radiator to drain the
coolant.
2.4
Disconnect the lower radiator hose, and
drain the remaining coolant.
2.5
Close the petcock, if equipped.
3.
Install the lower radiator hose.
4.
Fill the system with a coolant mixture of 50 per-
cent ethylene glycol and 50 percent water.
5.
Using ServiceRanger
1
, activate the HEV coolant
pump to purge any air that may be trapped in the
system. Run the cooling pump until the air
bubbles stop appearing in the reservoir tank.
6.
Check the coolant level, and add coolant as
needed. The system should be filled to the mid
level of the reservoir.
1 ServiceRanger is a service and diagnostic software program available from
Eaton Corporation. See the Eaton website,
for more
information.
Engine Cooling/Radiator
20
Business Class M2 Maintenance Manual, August 2015
20/4
Property of American Airlines
