I am wondering how often Prius drivers service their 12 volt battery? The 12 volt Prius battery being located under the trunk floor is kind of “out of sight - out of mind”. Although the Prius AGM battery case stays fairly clean and the terminals do not get heavily corroded, the terminals still get a layer of oxidation. It is the gray/black colored film that covers the terminals. This film creates resistance, voltage drop and shortens battery life. A clean terminal is bright and shiny. Servicing the battery generally involves: · remove the battery cables and hold-down bracket(s), · clean the top of the battery case, terminals and cable ends with a battery cleaner, · using a battery brush with soft brass bristles, lightly brush the battery terminals and contact areas inside the cable ends until they are bright and shiny, · reinstall the battery cables and hold-down bracket(s), · coat the reinstalled battery terminals and cable ends with a battery terminal protector. This is an inexpensive and easy task that if done once per year will prolong battery life and keep it in top condition. I just cleaned my battery which is now three years and 50,500 miles old. The resting voltage is 12.8 volts and the car has had no battery/electrical problems. Below are the three battery cleaning products I use. Edit: I meant to post this in the Gen III forum but it applies all Prii.
It is also recommended to provide an auxiliary 12v source to maintain the computer voltages while you have the Prius battery disconnected. In addition, there are procedures to use the display to test the voltage with load and without load which do not require any disconnects.
Have had mine 5 years. First clue 12 volt battery was nearly dead … rear hatch release worked poorly for months, and finally completely died. Bought a new Optima battery for $150 with coupon (Toyota wanted $200) from Advance Auto Parts and installed it myself … tricky but do-able. Anyone have info on rehooking the battery when you are supposed to be "sure it's in neutral before turning on the hybrid system??" I didn't, but everything seems to be working fine (after resetting the windows and rear hatch).
mine wouldn't operate at the door handle, i had to push the fob button. i had the mechanic replace the battery, never thought of cleaning the connections.
after 6.5 years and 88,000 miles the 12 volt battery was weak. First clue, the passenger door did not unlock to the touch, the trunk lid was hard to open. Twice when below zero outside I had to turn it over twice, the first time a red light on the power button. Local Toyota dealer replaced in 30 minues for 270.00, not bad since Amazon seemed to sell them for 178.00, then there is install....Sams club does not carry!
