What exactly is powering coil packs in our ICEs? With no alternator?

 

The alternator does not really power the coil packs in any car. The alternator charges/floats the 12V system. The 12V systems powers the coils until the 12V system voltage drops too low (dead battery). Cars will continue to operate without an alternator for that reason.

Like all other cars, the 12V system powers the coils in the Toyota Hybrids. The only difference is the 12V system is charged/floated by the Inverter/DC-DC converter off the HV system.

 

So it's charged by hybrid battery. I know 100% 12V battery does not.
Thank you.

 

I'm not quite sure what you're saying. Just to clarify...

The 12V system powers the coils. Period.

The 12V system is charged by the HV system via the Inverter/converter. That may come from the HV battery or MG1.

 

Keith, on this car, 12V can be acquired by various methods. I really do not want to spend time, but I had it done before and I know that 12V battery in the trunk is not supplying power to coil packs.
I am not saying coil packs are not 12V powered. I am simply saying - THAT 12V is coming from hybrid battery, not from 12V battery in the trunk. From DC/DC converter.

DC/DC Converter
Drops the maximum voltage of DC 244.8 V into DC12 V in
order to supply electricity to body electrical components, as
well as to recharge the auxiliary battery (DC 12 V).

Auxiliary Battery
Charged by the HV battery module power via the DC/DC
converter. Supplies power to the audio system, air
conditioning system (except the electric inverter compressor)
and the ECUs.

 

Really do not want to spend time? Then why did you ask the question?

No. It can't be acquired by various methods. It's ALWAYS from the 12V system.

Note that at no point did I say the 12V battery runs the coils. I said the 12V system.
The 12V battery is ALWAYS part of the 12V system. It's not like a switch flips and the 12V is not in the system. It's either charging or discharging according to load or 12V system float voltage.

If you want to follow your logic that the HV battery powers the coils, then you need to acknowledge that the "alternator" is powering the coils since it charges the HV battery, i.e., MG1 or MG2 depending on circumstances. This is flawed.

It's been demonstrated on this forum that someone can start and run a Camry hybrid with an inoperative DC-DC converter. What powered the coils then?

Gas-only cars will run without alternators.

Camry Hybrids will run without an operational DC-DC converter.

Until their 12V batteries are dead.