checking on 12v battery

[ukrkoz]

this is procedure for Prius, but it might as well work for TCH:
Checking 12v Battery Health You can easily check out your battery status/charging system using the MFD in maintenance mode. No tools required.

1. Get your Prius into "Accessory Mode" - Press the power button without touching the brake pedal.
2. Put the MFD into "Maintenance Mode" - Press and hold the "Info" button on the MFD while turning the headlights on and off 4 times.
3. Press the "Menu" field on the screen.
4. Press the "Display Check" field.
5. Press the "Signal Check" field.
6. The 12v battery voltage will be one of the items listed, it should be above 12 volts. If it is lower, either the battery needs replacement or the charging system is not functioning correctly - see step 7.
7. Put a small load on the battery by pressing the power button again without touching the brake pedal. The voltage should stay above 12v. If it drops significantly, you need a new battery.
8. Now get your Prius into "Ready Mode" - step on the brake and press the power button. The battery voltage should immediately rise to 13.8 volts (Your Prius uses constant voltage charging). If it is lower, the battery will never charge; if it is much above 14 volts, your 12v battery will get cooked.
9. Shutting the car down will reset the system back to normal operation.

1. There is a good chance that a variation of this procedure will work on a Camry Hybrid, Highlander Hybrid, or Lexus Hybrid as Toyota tends to be consistent.

One reported alternate sequence to get to the Maintenance screen is a sequence of screen touches:
"Push DISPLAY and then instead of Upperleft, Downleft,Upperleft, Downleft,Upperleft, Downleft try Upperleft, Upperright, Upperleft, Upperright, Upperleft, Upperright."

and on the costs note:

When I checked to see how much a 12v battery would cost to replace the one in my Toyota Camry Hybrid, I found out that it would be three times higher than most cars. The cost will be over $360. (Most 12v auto batteries sell for around $90).

Doesn't that sound like Toyota is bleeding the same people who are trying to conserve energy? With all the costs involved in Hybrids, I don't think we are saving that much.

they have alternative battery from Optima for only $180, but terminal cable has to be replaced to match.