Prius Auxiliary Battery Adventures.
Some of you may know, but the 12v (AKA Auxiliary) Battery is a bit of a strange animal. First of all it is an AGM and has a vent tube. Secondly the battery post are about half of normal size. The factory battery is a low AH/CCA battery and it is reported that vehicles without the smart key system have even smaller ones. While direct fit batteries are becoming more common (I found a listing for an Exide and Bosch [which looks a lot like the Exide] in addition to Toyota and Optima) Optima is a popular choice offering slightly higher capacity. Even before the specific Optima was introduced people were modifying the 12V battery cable to install a Honda spec Optima - this is no longer necessary with the Prius specific Optima.
Also, this battery implementation is a bit different from a normal car battery. It is not my intent to explain the Prius starting and charging system - plenty of that on the internet, but it neither runs a starter or gets charged by an alternator.
Having seen a drop in mileage and gotten the red triangle a couple of times (that is bad) I did some of the common test and found the existing battery dropping below 11volts under a headlight load after an overnight rest. Charging and conditioning did not seem to improve the situation. So I chose to replace the existing battery with the Optima. This Optima is listed for cars with the smart key system (SKS) however folks have reported successfully fitting it to non SKS cars by replacing or modifying the battery tray - which is really more like a bracket that bolts to the bottom of the quarter panel.
Armed with an Advanced Auto Parts discount code - I went off to the AAP website and placed an order for store pickup ant the only store in the immediate area showing it in stock. Upon arriving at the store they were unable to locate the battery and had to order it from the warehouse, not a big deal since It wasn't dead in the water. (In retrospect I thought it was odd this store showed stock on it - it is not in an area where I would expect this battery to be a big seller).
This morning the Battery arrived at the store and I went and got it.
Hmm - about 4 months old and kind of dusty.
Battery Pre-Charge status.
Lets see if we can fix that up.
Getting close.
Finally.
Cleaned up and ready to go in...
Optima - if you are reading this... it would be nice if you could stick the stickers on straight for $200.00.
And in the new home.
As a side note some have reported that Johnson Controls is also making the Toyota replacement Batteries. The battery in the car was a replacement dated I/12 and was clearly marked GS-Yuasa - Made in Japan.
Some of you may know, but the 12v (AKA Auxiliary) Battery is a bit of a strange animal. First of all it is an AGM and has a vent tube. Secondly the battery post are about half of normal size. The factory battery is a low AH/CCA battery and it is reported that vehicles without the smart key system have even smaller ones. While direct fit batteries are becoming more common (I found a listing for an Exide and Bosch [which looks a lot like the Exide] in addition to Toyota and Optima) Optima is a popular choice offering slightly higher capacity. Even before the specific Optima was introduced people were modifying the 12V battery cable to install a Honda spec Optima - this is no longer necessary with the Prius specific Optima.
Also, this battery implementation is a bit different from a normal car battery. It is not my intent to explain the Prius starting and charging system - plenty of that on the internet, but it neither runs a starter or gets charged by an alternator.
Having seen a drop in mileage and gotten the red triangle a couple of times (that is bad) I did some of the common test and found the existing battery dropping below 11volts under a headlight load after an overnight rest. Charging and conditioning did not seem to improve the situation. So I chose to replace the existing battery with the Optima. This Optima is listed for cars with the smart key system (SKS) however folks have reported successfully fitting it to non SKS cars by replacing or modifying the battery tray - which is really more like a bracket that bolts to the bottom of the quarter panel.
Armed with an Advanced Auto Parts discount code - I went off to the AAP website and placed an order for store pickup ant the only store in the immediate area showing it in stock. Upon arriving at the store they were unable to locate the battery and had to order it from the warehouse, not a big deal since It wasn't dead in the water. (In retrospect I thought it was odd this store showed stock on it - it is not in an area where I would expect this battery to be a big seller).
This morning the Battery arrived at the store and I went and got it.
Hmm - about 4 months old and kind of dusty.
Battery Pre-Charge status.
Lets see if we can fix that up.
Getting close.
Finally.
Cleaned up and ready to go in...
Optima - if you are reading this... it would be nice if you could stick the stickers on straight for $200.00.
And in the new home.
As a side note some have reported that Johnson Controls is also making the Toyota replacement Batteries. The battery in the car was a replacement dated I/12 and was clearly marked GS-Yuasa - Made in Japan.
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