Triangle of Death 2012 Prius 175,000 Miles

I understand how Hybrid works. The 12V battery is only to start computer and contactors. That's why we heard clicking noise on the back when the car just started. The HV battery is the one that start the MG1 to start the engine, etc. The DC to DC converter works like Bank/Alternator that convert high voltage to 12V lines and power all 12V lines in Ready mode. The 12V battery is normal AGM battery with a small 35Ah or 45 Ah capacities. Nothing special. In facts, some people are too cheap to buy Yuasa AGM battery and replace it with regular wet cells made by Bosch or Varta. It works but I dissagree with them because of safety reason.

 

Then you SHOULD know that 11volts for a 12v volt computer is NOT good.

 

Yeah, I know. But for scientific purpose, Physics guides us well. The open voltage of fully charged AGM battery is actually > 13V. 11V reading in closed circuit is nothing to worry about. 11V in an open circuit means one of the cells died or dying, but fine in closed circuit because it depends on the load

 

Its REAL world that's important. All that will do is get you to spend more money
and time looking at something that's not important. 1 or 2 tenths of a volt are a
huge deal for a Prius.
Many have spend hours, days and weeks and a lot of money trying to fix a symptom
instead of the cause of their issue. When several people inform them it's the low 12v
battery and they keep saying no, but eventually replace the battery, all the symptoms go away...

 

Consider getting an electronic load tester, or have it tested for free at automotive retailers, they often have such testers. I’m using Solar BA5 (current model BA9). It’s a small, relatively cheap device you connect directly to battery posts, set some parameters (battery type and rated CCA), then test. It shows voltage, current CCA and gives a verdict, either pass, pass but needs charge, or fail.

 

I got C1241 DTC that regular scanner cannot pick it up. It does not show check engine light either and I failed MOT test because of such pending Cxxxx code. I reset it with Carista App. It was caused by removing the quick connect on my 5A trickle charger without disconnecting the battery cable completely. I was just too lazy to adjust the clock if removed the cable completely. Yes, it is true that dying battery can cause wacky error codes. We can test the battery in Autozone or Advanced autoparts. Just tell them what is the CCA because they don't even know where to find the battery information.

 

They cannot test the battery correctly.
IT IS NOT THE SAME FOR A PRIUS! You're just not really getting that.....
See post 20

 

I think battery test is the same in all cars just like @Mendel Leisk said. He uses BA5 tester and it works for any Lead acid battery. What will not work is testing the DC to DC converter because Autozone and Advanced Auto employees only know how Alternator works. Testing the battery is either when the car is off or remove the battery completely from the car.
The DCtoDC converter is rated at max 100Amp only for the 12V lines. That's whey we are supposed to never jump start other regular car with hybrid. We can jump start other hybrid or EV.

 

Tell everyone what IS the correct way to test a 12v battery for a Prius.

 

See post 27

 

Are you responding to post #28 or post #29?

 

"Minus 105," he said.

At first there was stunned amazement, then first one professor laughed, then another then another, till they were all rolling about holding their sides.

None of them had heard that one before.

 

Harbor Freight now has a 35 Ah agm battery about the size of an oem battery for $76 before coupons.



All value added calculations must be redone!