My 12V Battery is dying

I don't know....

 

I wonder if some future decision to compensate owners who paid to have a defective part/design fixed would be in favor of the dealer fix, or the do-it-yourself/eBay fix? Future compensation is probably only wishful thinking.

@soft_r did a nice video on taking the console apart.

I wonder what the Mass criteria is for passing state inspection? I'm under the impression it was only smog in NY, but I could be wrong. You can get a message for any tricky tacky thing. I would think it would just have to pass the engine readiness test when they plug in their obdc reader.

 

It depends on the shop, state rules, and regulations. Most shops around here will automatically fail you, if the check engine lamp is ON. They won't even pull it into the shop, but they won't charge you either. If you insist, they'll charge you then fail you - though out here the issue needs to be smog related. How would you know, unless you've got your own scanner and know what codes was thrown and if they are smog related? Whomever signs-off on that certification is liable - they don't want to lose their license and livelihood over stupid stuff, so safer to simply fail you.

 

I think if you don't have a check engine light, and the engine says it's 'ready', with zero engine dtcs when he plugs his machine in, there might be a chance that you're okay. After all, how many ECU's are there in the car? Should the car fail state inspection because there's a code for a faulty window operator? But that would be logical, and who knows what the state's view is.

 

Maybe get a decent prosumer level battery tester, see where yours is at. They test voltage AND Cold Cranking Amps, and usually will give a verdict on it's condition. Here's an example, an updated version of what I'm using.

Also, test for how much amperage is constantly being applied to the battery, when the car's completely off. It should be around 20 milliamperes, 40 max. A video on that process:

 

That could be awesome. I wonder if you can drive around with it removed?

 

Looks to me more like a return of gen 2's brake backup power supply, only now feeding some other stuff besides the brake actuator.



The gen 2 thing was a box of capacitors and a DC/DC converter that could take incoming 12 VDC and boost it to store a bunch of energy in the caps. Then, in the event of a 12-volt system failure, it could dole out the stored energy at 12 volts again for however long it was meant to hold up.

That approach of boost-converting input voltage to charge a big capacitance, and then buck-convert it out at the right voltage later, would make it sort of a cousin of the capacitor-based jump boxes you've been able to buy for several years or so.

Judging by the selection of live data it can give you, it's a fairly involved piece of kit:

• Total Distance Traveled
• Total Distance Traveled - Unit
• IGR Switch
• H Switch
• BR Signal
• RO Signal
• Door Unlock Operation Request Signal at Collision
• Door Courtesy Signal
• Wake Up Request Signal
• DC/DC Converter Status
• System Voltage Relay
• System Voltage
• AECU Relay
• AECU Output Voltage
• AECU Output Current
• A2ECU Output Voltage
• BECU Relay
• BECU Output Voltage
• BECU Output Current
• CECU Relay
• CECU Output Voltage
• CECU Output Current
• AACT Relay
• AACT Output Voltage
• AACT Output Current
• BACT Relay
• BACT Upstream Through Relay
• BACT Downstream Through Relay
• BACT Output Voltage
• BACT Output Current
• CACT Relay
• CACT Output Voltage
• CACT Output Current
• Dark Current Cut Relay
• Backflow Prevention Circuit Downstream Relay
• Backflow Prevention Circuit Upstream Relay
• Inflow Prevention Relay
• Charging Circuit Information
• Cell Balance Circuit Information
• Reset Prevention Circuit Information
• Control Status
• BUV Voltage
• PWB Voltage
• PWB Current
• Capacitor Voltage
• Capacitor Current
• Capacitor Temperature
• Capacitor Resistance Calculation Value
• Capacitor Capacity Calculation Value
• Unit Temperature 1
• Unit Temperature 2
• Protection Circuit Diagnosis Signal (GND Overcurrent Detection)
• Protection Circuit Diagnosis Signal (PWB Overvoltage Detection)
• Protection Circuit Diagnosis Signal (PWB Overcurrent Detection)
• Protection Circuit Diagnosis Signal (PWC Overcurrent Detection)
• DC/DC Converter Step Up/Step Down Primary Power Supply Side Ground Fault Diagnosis Result
• DC/DC Converter Step Up/Step Down Capacitor Side Ground Fault Diagnosis Result
• DC/DC Converter Step Up/Step Down GND Side Ground Fault Diagnosis Result
• DC/DC Converter Step Up/Step Down Discharging Diagnosis Result
• DC/DC Converter Step Up/Step Down Charging Diagnosis Result
• Capacitor Cell Overvoltage Diagnosis Result
• Reset Prevention Circuit Short Diagnosis Result
• AACT Output Terminal Ground Fault Diagnosis Result
• AECU/A2ECU Output Terminal Ground Fault Diagnosis Result

I got that info from somebody's copy of the Repair Manual, which isn't where you find the detailed explanations of what things are for and why and how they do it; those details are in the New Car Features manual, which the Repair Manual just assumes you've already read so you already know.

I wasn't quite curious enough to re-up my own TIS subscription and look this thing up in NCF, but I'm almost curious enough, and if someone else looks it up I'll definitely be interested in those details.

Toyota Service Information and Where To Find It | PriusChat

Those motor capacitors are really doing something more interesting and geeky than that. They couldn't really just smooth out the voltage sag, because the voltage coming to the compressor is alternating current; there would need to be a whole inverter connected to the cap if you wanted to use it to supply non-saggy AC—and it'd have to be a physically yuge cap.

The start and run capacitors are really just big enough to make a slightly-lagged version of the incoming AC waveform: also reversing direction 120 times a second, but just slightly phase-shifted from the supplied one.

A motor fed only from incoming AC that keeps exactly reversing itself wouldn't have much reason to turn (think a crankshaft at top or bottom dead center). Industrial motors (and Prius MGs) are three-phase, which totally solves that problem: they have three windings spaced around the stator and are fed with three copies of the same waveform but 120° apart, and that naturally spins the rotor around.

But a motor fed from a single-phase supply needs some trickery. The usual trick is to give it two windings with some angle between them, and feed one winding the incoming AC voltage directly, and feed the other one a slightly-lagged version of the same waveform, courtesy of the capacitor. That's enough to pull the rotor around and spin it.