What powers the lights, wipers, etc...

[Socalredneck]

Hey Guys,

Sorry, but I'm still fairly new to my '01 Insight (but I LOVE it). My car has 175+K miles on it, and have only been driving it about a month. So I don't know the history or condition of the IMA batteries.

But I'm curious to know what powers all the lights & accessories on the car, the head-lights, turn-lights, brake-light, wipers, radio, 12v adapter on dash, etc.... Does it come from the IMA batteries or the 12v battery under the hood?

The reason I ask it that it seems to be harder for my IMA batteries to fully charge or stay charged, when I'm running every thing. I've noticed when using the Auto Stop, at night with lights on, radio on, etc, that I can stop at a signal light with near full IMA batteries, then pull away a few minutes later and the batteries will quickly drop a couple bars. This makes me wonder if the lights & accessories are tied in with the IMA batteries and not powered off the engine battery.

Thanks!

[TopFuelTim]

Originally Posted by mfelkins

Hey Guys,

Sorry, but I'm still fairly new to my '01 Insight (but I LOVE it). My car has 175+K miles on it, and have only been driving it about a month. So I don't know the history or condition of the IMA batteries.

But I'm curious to know what powers all the lights & accessories on the car, the head-lights, turn-lights, brake-light, wipers, radio, 12v adapter on dash, etc.... Does it come from the IMA batteries or the 12v battery under the hood?

The reason I ask it that it seems to be harder for my IMA batteries to fully charge or stay charged, when I'm running every thing. I've noticed when using the Auto Stop, at night with lights on, radio on, etc, that I can stop at a signal light with near full IMA batteries, then pull away a few minutes later and the batteries will quickly drop a couple bars. This makes me wonder if the lights & accessories are tied in with the IMA batteries and not powered off the engine battery.

Thanks!

As you think, lights and accessories are powered by the 12V battery. However, the 12V battery is replenished from the 144V IMA battery through the DC/DC Inverter.

MY 0.02 worth,
Tim Glover

[Socalredneck]

Wow Tim thank you for your FAST response!! That makes total sense, I wondered how they could design the car to have an Auto Stop, yet run lights & accessories for an unknown period of time. I feel much better now knowing.

So is the 12v battery always charged by the inverter, or is there an alternator for charging the 12 battery too? Sorry, I haven't looked or investigated that yet.

[TopFuelTim]

There is a tremendous amount of information on this forum, and it is very interesting if you like these cars. They do not need an alternator, as the 10 kilowatt motor / generator supplies the power to the IMA battery any time you coast or tap the brakes. The DC-DC inverter then charges the 12V battery from the IMA battery, as needed. I think it actually does it too much, as when I checked my last 12V battery that failed, the electrolyte was down below the plates on each end of the battery.

My 0.02 worth,
Tim Glover

[Socalredneck]

Thank you Tim!!! That was worth more then $0.02, so I'll have to owe you

I'm trying to learn as much as I can, but there is soooo much to learn about them. But I'm loving mine.

[Eli]

More or less just a semantics issue, but technically the DC-DC usually draws power from the IMA motor. It only draws power from the IMA battery when in auto-stop, during assist, during regen and when the battery SoC is above ~80%.

[TopFuelTim]

Originally Posted by Eli

More or less just a semantics issue, but technically the DC-DC usually draws power from the IMA motor. It only draws power from the IMA battery when in auto-stop, during assist, during regen and when the battery SoC is above ~80%.

Hi Eli,

I sit corrected : ). I appreciate the information, as I now know a little more about my car. I am still amazed at the thought and engineering that went into making these cars.

Tim

[Eli]

And to further clarify my clarification.. lol.

During assist, the 12V system load is shifted to the IMA battery to further help the engine.

During regen, the amperage to charge the 12V system is taken "off the top" so to speak, since it's "free".

I first noticed this while experimenting in my driveway. Commanding a bit of regen with MIMA, and the radiator fan comes on, and suddenly the regen amperage us reduced by 3 amps.

[RedJellyBean]

Originally Posted by mfelkins

Hey Guys,
I'm curious to know what powers all the lights & accessories on the car, the head-lights, turn-lights, brake-light, wipers, radio, 12v adapter on dash, etc....

Voodoo magic and IMA fault codes.

[Hitech]

And just to worry you a little bit ,your IMA is telling you something by your symptom. I would invest in a grid charger if I were you. Your batteries are out of balance at least. (read up on "Grid chargers" on this forum)