Check Hybrid System

There is nothing that you can do. Do NOT clear the trouble codes. If you can not drive the car to the dealership, have it towed. If it is covered by the 20-year extended warranty, the cost of towing it to the dealership will also be covered.

 

Pay attention if 20 yrs of car experience. Should be good . Don't mess w anything have a print out or picture of codes on a machine. Welp ya might consider it today . Dishonesty is common searched for trait employers look for especially in current climate. criminal activity of certain types is now acceptable.

 

the 12v is charged through the inverter by the hybrid battery.

the gold standard is a free load test of the 12v at many auto parts stores.

keep in mind that to get correct prius trouble codes, you need a prius aware scanner.
the codes you have pulled may or may not be correct. and a bad 12v can cause bad codes as well.
once armed with the correct codes, finding help on the net is usualy fairly easy, or you can rent the service manual from toyota if you can't find one for free

 

you should get a reading in the 13+ -14v when the car is ready, iirc.

look into autel. there are some threads here that say it can do everything. tech stream is the best and cheapest, but can be a tough setup if you aren't computer savvy.

it's possible that your codes are good, but how to know? i'm not familiar with ipm symptoms other than failing under hard acceleration

 

it rules out the inverter, but idk if it rules out the ipm, or what role it plays

 

have you read the ipm (intelligent power module) tsb/extended warranty?

 

i don't qualfy, i mean understanding what the ipm does.

watch

266917_Intelligent_Power_Module_settlement_MC-10240055-9999.pdf

ipm-inverter-needs-replacing.248405

watch

 

The terminology can be confusing here. When you check the 12-volt charging voltage, you are checking the operation of the DC/DC converter. If you buy the entire shiny "INVERTER WITH CONVERTER ASSEMBLY", that DC/DC converter is included; it's the thing bolted to the bottom. But it isn't anything to do with the codes you have.

When people say "the inverter", they can mean a couple of things: either the whole shiny box (which includes the DC/DC 12V converter), or just the actual power electronics for the motor-generators (the rest of the stuff in the shiny box, but not the DC/DC 12V converter).

The "rest of the stuff in the shiny box" is what you see here within that central box "INVERTER WITH CONVERTER ASSEMBLY": a boost converter, an inverter circuit for each MG, and an "MG ECU" controlling it all.



Notice that diagram doesn't even show the DC/DC 12V converter, even though it's also part of the "INVERTER WITH CONVERTER ASSEMBLY". There's a separate diagram that shows only that part, and not the other stuff:



The MG ECU makes a cameo appearance in that drawing too, just because the NODD and VLO circuits for controlling the DC/DC converter happen to physically pass through it, but other than that it's not involved.

For each motor generator, six transistors are needed so that the DC supply can be sent in either direction through each of the MG's three phase windings, arranged like this:



These are big insulated-gate bipolar transistors (IGBTs). There are two MGs, so there are a total of twelve IGBTs controlling them, six for each MG.

Also, there's that thing called the boost converter, which uses two more IGBTs. Its job is to take the roughly 200-volt battery voltage up to more like 650 volts for the MG inverters. In fact, it's bidirectional: it can also convert the higher MG voltage back down to the battery voltage while regenerating and charging the battery.



So inside the inverter assembly, ignoring the 12V DC/DC converter which is a different thing, there are a total of 14 IGBTs (six for each MG and two for the boost converter), and associated electronics for switching them, monitoring their temperature, and so on. All 14 of those are built into one big Integrated Power Module (IPM), which for gen 3 looks like this:



The three big rectangular features down the centerline are the groups of IGBTs (or leading to them, on the side you can't see against the heatsink). They're too small in the picture to count the transistors in each, but you can see two of them have tripled-up components to their left: those are the two groups of six, serving the two MGs. The one remaining has doubled-up components to its left, and is the group of two IGBTs making up the boost converter.

That whole thing is the IPM. You can see it even has hose nipples sticking out where the coolant hoses connect: the water-cooling heatsink is part of the IPM. (The 12V DC/DC converter ends up bolting to the bottom of that heatsink, so it gets cooled too. The yellow stencil in the picture is what you use to apply the right amount of heatsink compound before bolting them together.)

The big reactor and capacitor shown as parts of the boost converter are not on that IPM assembly; they are separate big parts also inside the inverter case.

Some people read "IPM" as "intelligent power module" instead of just "integrated", but it doesn't have a whole lot of 'intelligence' to it, other than doing some monitoring of the temperature and operation of its big IGBTs. Most of the inverter's 'intelligence' is in the MG ECU, which sits on a bracket up above the IPM, and looks like this:



(The thing off on the left is the current sensor, another separate part in there.)

So that's the lay of the land. Now, when something on the IPM fails, depending on how heavy the power flow is at the time, it can be a pretty big boom. Sometimes they only will have to replace the IPM. Sometimes it will have damaged the MG ECU mounted above it, or the current sensor mounted near it, and one or both of those will also have to be replaced. Sometimes it even damages the metal case, in which case you get a whole new shiny assembly. It's all covered under the warranty extension in any case. Their instructions tell them how to evaluate which parts were damaged and replace whatever's needed.

Your code P0A7A is easy to understand from its fortune cookie, "generator inverter performance". There's been a failure in the part of the IPM that runs MG1.

Your P324E code has a fortune cookie mentioning the MG ECU. That may have taken some damage, then.

The P0A94 is the code that often misleads people, because that code's fortune cookie (standardized by SAE because it's a P0 code) is "DC/DC converter performance". And nearly always, in a Prius, when we talk about "DC/DC converter", we mean the one producing 12 volts and charging the aux battery.

And nearly always, we say "boost converter" when we mean that voltage-boosting section of the IPM. (If you think about it, that is another DC/DC converter too, just one that converts 200 VDC to 650 VDC and back again.)

The "DC/DC converter" that the P0A94 code is talking about is the high-voltage boost converter, not the low-voltage 12V converter. So it's that other group of IGBTs on the IPM. And you don't learn anything about it by testing the aux battery voltage, because that's just testing a different thing.

I have been guilty of spreading the confusion myself in some of my older posts. Before I realized P0A94 is about the boost converter, I thought "DC/DC converter" had to mean the low-voltage one. Live and learn.

 

i think the naming confusion comes from toyota calling it the 'intelligent power module', at least in the 'customer confidence program 23TE02' linked above

 

Yeah, searching around for IPM shows "integrated" and "intelligent" are both in common use.

That's pretty much a harmless naming confusion (unless somebody assumes the 'intelligent' means it's a computer or something, and even then, what's the harm?).

The more troublesome confusion, on PriusChat anyway, is what the P0A94 "DC/DC converter performance" code pertains to. It isn't the "DC/DC converter" as Toyota uses the term, it's the boost converter, on the IPM. (Which is a DC/DC converter according to SAE, and SAE assigns the fortune cookies for P0 codes.)

So people waste time measuring the aux battery voltage, which has nothing to do with the code.

 

So I guess it's in the inverter which are plentiful and maybe free. I might have one gen 3 inverter here a good one

 

pleasure