[ldepason54]

Hi I wanted to bleed my cooling system and was wondering if it’s okay to keep the battery charging with another vehicle via jumper cable since the heater fan need to be on high for around 12 min which could drain the battery pretty fast. Or do I need a battery charger?

[jsunma]

IMO, unless you have reason to believe that your battery is on its last legs, or you're doing more than just doing the prescribed bleed procedure, you should not have to worry about your battery dying while bleeding your cooling system.

Others may have additional opinions, but tying your car to another car with jumper cables while doing this is just asking for trouble.

[Serf27]

Agreed with with first part above^.

The battery should be fine for the bleed procedure if it’s in good condition.

I have used other running cars to maintain batteries via jumper cables on the E9X. Never had an issue.