BMW I01 Product Information page 172

I01￿High-voltage￿Components
11.￿Cooling￿the￿Electrical￿Machine
Components
The￿electric￿coolant￿pump￿has￿a￿power￿of￿80 W￿(Manufacturer:￿Bosch).￿The￿coolant￿pump￿is￿activated
by￿the￿EDME￿control￿unit.￿For￿this￿purpose,￿the￿coolant￿pump￿and￿the￿EDME￿control￿unit￿are
connected￿via￿a￿direct￿line.￿The￿electric￿coolant￿pump￿can￿be￿activated￿at￿varying￿power￿by￿pulse-
width￿modulated￿signals.￿The￿voltage￿supply￿of￿the￿coolant￿pump￿is￿effected￿via￿terminal￿30B.￿The
installation￿location￿of￿the￿coolant￿pump￿is￿at￿the￿rear￿right.
The￿expansion￿tank￿is￿located￿in￿the￿space￿below￿the￿engine￿compartment￿lid￿on￿the￿left.￿There￿is
no￿electrical￿level￿sensor￿installed￿in￿the￿expansion￿tank.￿But￿there￿is￿the￿following￿special￿feature
to￿be￿noted￿for￿Service:￿A￿loss￿of￿coolant,￿for￿example￿due￿to￿a￿leak,￿in￿the￿cooling￿system￿is￿not
identified￿directly￿due￿to￿the￿lack￿of￿an￿electrical￿level￿sensor.￿Instead,￿in￿the￿event￿of￿coolant￿loss
the￿temperature￿of￿the￿cooled￿components￿(electrical￿machine,￿electrical￿machine￿electronics,
convenience￿charging￿electronics,￿range￿extender￿and￿the￿range￿extender￿electrical￿machine
electronics)￿rises￿above￿the￿normal￿operating￿range.￿In￿this￿case￿the￿power￿of￿the￿electric￿motor￿is
reduced￿and￿a￿corresponding￿Check￿Control￿message￿is￿issued.￿The￿Service￿employee￿must￿check
the￿following￿fault￿causes￿during￿troubleshooting:
• Loss￿of￿coolant,￿e.g.￿by￿a￿leak
• Coolant-air￿heat￿exchanger￿blocked
• Electric￿fan￿does￿not￿work￿or￿is￿restricted
• Coolant￿pump￿does￿not￿work
• Coolant￿lines￿or￿connections￿damaged
• Components￿to￿be￿cooled￿faulty￿(electrical￿machine,￿electrical￿machine￿electronics,
convenience￿charging￿electronics,￿range￿extender￿electrical￿machine,￿range￿extender￿electrical
machine￿electronics).
If￿excess￿temperature￿is￿displayed￿in￿the￿cooling￿system￿of￿the￿electric￿motor,￿then￿this￿may￿have
several￿causes,￿including￿also￿the￿loss￿of￿coolant.￿Therefore,￿during￿troubleshooting￿all￿components￿of
the￿cooling￿system￿must￿be￿checked￿systematically.
The￿familiar￿mixture￿of￿water￿and￿antifreeze￿and￿corrosion￿inhibitors￿in￿BMW￿vehicles￿is￿used￿as￿a
coolant.
When￿filling￿the￿cooling￿circuit￿of￿the￿electric￿motor￿use￿the￿special￿tool￿for￿vacuum￿filling￿according￿to
the￿repair￿instructions.
Perform￿a￿bleeding￿after￿filling￿the￿cooling￿circuit,￿as￿well￿as￿after￿replacing￿components￿in￿the￿cooling
circuit.
For￿the￿bleeding￿the￿cooling￿circuit￿for￿the￿electric￿motor￿in￿the￿I01￿follow￿the￿same￿procedure￿as
for￿conventional￿vehicles.￿There￿is￿a￿Service￿function￿in￿the￿diagnosis￿system￿for￿the￿activation￿of
a￿bleeding￿procedure.￿This￿consists￿of￿appropriate￿activation￿of￿the￿electric￿coolant￿pump￿(varying
engine￿speed,￿defined￿duration).￿This￿bleeding￿procedure￿can￿also￿be￿activated￿without￿the￿diagnosis
system.￿The￿following￿procedural￿steps￿must￿be￿carried￿out￿here:
1 Connect￿the￿charging￿plug￿to￿the￿vehicle
2 Switch￿on￿terminal￿15￿(only￿ignition,￿no￿driving￿readiness)
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