12 Volt Battery Issues / Replacement

[user 340]

They couldn't do it immediately because they need to charge my 12 volt (aux) battery first to full.
Even though I drive it enough (imo) to keep it charged, it wasn't enough to do software update.

Hmmm... maybe your 12V battery is on its last legs or else there is a problem with its charging system.

 

[Dsinned]

My 2012 RAV EV (purchased new in November 2012) had a complete and total electrical failure last January due to my car's 12V battery inexplicably discharging to a very low level (even while actually driving the car). I was monitoring the voltage while driving with a DCV digital readout device plugged in to the cigarette lighter power socket at the time.

To best of my knowledge, based on information given on the TMS forum, 12V batteries in Tesla Model S cars are susceptible to going EOL within ~2 years from brand new. Apparently, Tesla recommends 12V battery replacement at much more frequent intervals to preclude this problem.

After having my car towed to my local Toyota dealer, and recharging the 12V battery manually, no trouble was found with the onboard charging system, but they replaced the 12V battery anyway. Me thinks there is something to the notion that Tesla drivetrains have a very high vampire load on 12V batteries, and the number of charging cycles they can withstand is really quite limited.

I have not heard of any other RAV EV premature 12V battery failures like mine, so this is just a heads up to all fellow forum members.

 

[TonyWilliams]

12 volt battery replacement is a "top ten" list item.

http://www.myrav4ev.com/forum/viewtopic.php?f=8&t=1589

This is mostly for prospective used buyers:


Issues with RAV4 EV:

1) Speed sensor - RECALL ITEM - vehicle will pop into neutral and stop, power steering disabled)

2) Gateway / communications "ECU" (can disable vehicle, usually a Check EV light)

3) Motor / gear box noise (requires motor replacement)

4) Heater failure (which then takes out the DC to DC)

5) DC to DC failure

6) Onboard charger failure (can't recharge vehicle... except JdeMO equipped cars with CHAdeMO quick chargers)

7) Leaking oil from gear box (I've had this on both one RAV4 and our Mercedes B-Class ED that shares the same Tesla Model S drivetrain)

8) "CHECK EV SYSTEM" message du jour (requires four ON/OFF cycles)

9) Charge Timer

10) Entunes

11) 12 volt battery