12V battery not charging and P3001

A test would be to make the Prius READY, then measure voltage across the 12V battery. A correct reading would be ~13.8VDC, and if you see this reading then the 12V battery should be charging when the car is READY.

If you see a much lower voltage when the Prius is READY, that is evidence that the DC/DC converter within the inverter is not working, and that you would have to replace the inverter. However your car should have logged DTC that supports this finding, such as DTC P3125.

What is your means to retrieve the logged DTC?

 

This is evidence that the DC/DC converter is not working.

 

Check the 100A DC/DC fuse in the fuse box next to the inverter, take a voltmeter and measure both sides of the 100A DC/DC fuse to ground while in ready mode. Be careful not to short to anything with the meter probes 100A can instantly melt them. But if you see the 10v on the battery side, and 13.8-14V on the inverter side then the inverter is good, only a blown 100A fuse. However if you have 10V on both sides of the fuse, then the inverter most probably has a problem and the fuse is good.

Of course the easier way is to just check it with an ohm meter while the car is off, but in this case you must first remove the fuse. Do not check the fuse with an ohmmeter while it is still in the car, if it is open there will be voltage across the ohmmeter and they don't like that.

 

I thought we had a recent posting on where to measure the output of the inverter 12 V DC source? Or was that just the NHW20?

Bob Wilson

 

So we have one east coast inverter with failed DC/DC converter and at least one west coast inverter, same symptom. This is getting interesting.

Will you be disassembling the inverter to see what might have failed?

Bob Wilson

 

Cool. Pictures?

Can you identify where the 12 VDC comes out? See if you can trace it back to a set of circuits and test continuity.

Bob Wilson

 

Colonel,

Two things I have learned during my replacement of an inverter on a 2001 prius.

First, having borrowed obd2s from others, they do not register all the error codes. I don't know why. On some I only get 1 of the three codes in my Prius system. You may have other codes you are not aware of.... Just throwing this out there as a possibility, the obd2s I used were pretty cheap.

Second, my inverter failure was probably caused by a bad inverter coolant pump. I'd check yours to make sure it is working.

 

This is why I would pay shipping for the failed inverters and if available, failed inverter coolant pump(s). Hobbit's disassembly of an NHW20 inverter showed evidence of arcing on the 12 V DC-to-DC converter board. Having two failed units, I would like to map the coolant flow, converter location and see if a common failure mode can be identified.

As our NHW11s age, we are likely to see failure patterns that fall outside of the Toyota warranty intervals. Coolant aging that leads to jellified clumps is something Hobbit reported in his investigation and has been reported at least one other coolant change. The boy whose traction battery we swapped reported that a pH change can lead to a similar change in coolants used in solar collectors.

Bob Wilson

 

If the parts are of value to you, offer to buy them.

A pattern failure cannot be determined from two failed components.

Ask any competent engineer; they will tell you the same thing.

That has not been a significant issue in the field.

 

How much are you offering?

A journey begins with a single step followed by another.

ROTFLMAO! You have not offered anything for these broken parts and I suspect lack the ability to backup you posting.

Right, sure, of course. You are of course welcome to 'out bid me.' <GRINS>

What a lazy and exceptionally incompetent series of nonsense . . .

Put your money where your mouth is, son. Offer something on top of my offer to pay for shipping to Huntsville AL, 35802 <GRINS>

Bob Wilson

ps. Son, I've got your number and will enjoy your silly postings.

 

I have no need for failed components. You said you did. If they are worth something to you, and you aren't getting a response, offer to buy them. You may be successful. I sincerely wish you the best of luck.

Again, I am not trying to obtain parts. And there's nothing to "back up." You're trying to get somebody to give you some broken parts. I've suggested a method that may yield more success. Feel free to ignore it if it doesn't suit your needs. I won't be offended.

With all due respect to any personal situation of yours that might have triggered such an outburst, neither the language that you have used nor the anger that you appear to be expressing are appropriate to this thread or this forum under any circumstances.

See above. You may also wish to try wrecking yards in your area. Good luck.

 

Exactly . . . all hat and no cattle.

Bob Wilson

 

From the manual for P3001:

The HV ECU checks the battery voltage circuit for failure by comparing with the inverter voltage.

You replaced the inverter. You replaced the battery ECU. But are all of the voltage sensor wires properly in place? I'm not very familiar with Gen I, but this seems like some sort of communication, wiring, or sensor problem.