Hey, I've got an '03 Insight with 84,000 miles on it. The IMA battery went out, luckily under warranty...I was told it was around $5000 parts and labor.

2 weeks after it was replaced my 12v went out. It wont hold a charge anymore. I would jump start it and drive around, then as soon as I shut the car off it wouldn't restart.

Here's my question:

After I jumped my car it ran fine...it even shut off at stoplights and restarted. But when I shut the car off with the key it wouldn't restart. Why then, would it restart on its own after the light turned green, but not after I turned the key off.

Does that 12v not restart the car at that point?
Why is a 12v even needed?
Does it have something to do with cold cranking amps?
Can I do away with the 12v somehow?
Is that too many questions in a row? ha

I have alot to learn about my car....but I loooove it!!

 

Replace that 12v battery now!

$75 is a lot cheaper than the battery pack.

All the hybrid battery pack does is propel the Insight. If you were to see the battery pack behind the seats, you would see fans and boxes networked to your Insight's computer system - all of them powered by your 12v battery.


from www.99mpg.com


I hope it's obvious that the 120 D-Cells in that battery pack are maybe 20% of the compartment - the rest is supporting it.

I've been advised to do a trickle charge overnight on my 12v battery every few weekends to prolong it's life...and indirectly the hybrid battery pack.

 

Thanks alot! That makes sense. I'll be sure to keep a close eye on this new 12v so that in a couple years it doesn't do any damage to my new ima battery...because by then im sure it wont be under warranty!

 

EmbraceEphemeral,

In the picture above, the battery pack is below the two boxes on the right
- BCM box determines the state of charge. It "forgets" and you have a forced recal if 12v battery is disconnected - don't worry about that.
- MCM box regulates the Assist and Charge
- MPI on extreme left transmits battery pack power to the motor and generates a lot of heat
- heat sink and fan is immediately to the right of MPI.
- DC/DC converter is to the right of heat sink. Converts 12 volt/144 volt.


Other considerations include making sure the batteries don't get too hot in the summer - don't let the passenger seat all the way back (and cover the battery pack inlet). Some A/C use in 95F days or hotter helps the batteries, as Honda limits the Assist when they get hot (120F?)

 

Oh ok, luckily its cooling off, but next summer i'll be more conscious of keeping it cool!!

Speaking of cooling off, i've been reading about the "warm air intake" and im possibly considering it but im not sure how I feel about it...

Is it stressful on the motor? I would just be afraid that it would be running to hot.
I had the idea the create an intake system the would draw cold air and/or hot air. I want to put a temp gauge in the duct and have a simple electric valve to select the proper mixture of hot and cold air depending on the outside temp.
Being a fabricator, i want to make it a very quality job.
Does this seem like a worthwhile idea?

I really appriciate your feedback! Hopefully i'll eventually know enough to help other hybrid fans!

 

I get the 12v battery load tested every other oil change just for that reason. My car is WAY out of warranty now (5.5Y/120k miles), so if the IMA blew up, I'd basically have to get a new car.