Need a Pro's Opinion - '05 Prius with new HV/LV batteries - Not starting unless battery reset!??

welcome! no way of knowing until she gets the codes read. could be a bad doorman, it happens often enough.
you can check the inverter pump by making the car ready and removing the reservoir cap to see if the fluid is swirling.

 

A high voltage leak will cause this behavior.

Most likely the leak is coming from the just installed battery. Other common leak sources are the AC compressor and the transmission.

O'reillys generic code reader can not capture all the Prius codes. The high voltage leak code is P0AA6. There are sub or detail codes that go with the main code. The sub codes will help pinpoint the source of the leak.

You need to have the codes read with a proper scanner. Most members here use a MIni VCI cable that sell on ebay or Amazon for less than $25.

Brad

 

The normal scanners that the auto parts stores have cannot read all of the ECU's that a Prius has. If there is lights on there IS a code. Without that code there isn't much we can do. Unless you can find someone local with Techstream on a computer the only other option would be the dealer. I will say that I experienced the same issue twice with my dads 05 and with another 05. My dads was caused by a leaking module in the HV battery and the second one was caused by a voltage leak detected in the transmission. But like I said the only way to tell is if you have the codes, and if it is a HV leak code there will be a secondary code that will tell you where it is coming from.

 

The P3009 and P0AA6 codes are the same thing. The P3009 was used for the Gen I Prius and it is listed in my 2004 Gen II repair manual. After that they used the P0AA6.

The high voltage is isolated from the rest of the car. Unlike the 12 volt system the body is NOT used for ground. A HV leak means there is a path to ground. A battery that has leaked electrolyte can provide this path. The AC compressor has a high voltage motor inside. Using the wrong conventional PAG oil can cause a HV path to ground. The correct ND11 oil is non conductive. The electric motors inside the transmission can burn off their insulation and then leak to ground. This is not common.

Here is a you tube video showing Dorman's test. The problem is your car is taking too long to produce the code. You might have to wait until the code pops up quicker. The Sub codes will show where the leak is coming from.

Brad

 

this is one of the problems with dorman. you have to go back to your installer. if he does not have tech stream diagnostic, the burden falls on you.

 

correct.

 

Try the test two or three more times. Give it lots of time in ign on Ready off. You want to be able to reproduce the results consistently. The transmission has been ruled out. That is good because you have avoided the most expensive repair. With ready on in neutral power was not being sent to the transmission so the leak had to be somewhere before the transmission. That leaves the battery, inverter, wiring, and AC compressor.

The simple test for the AC compressor is to unplug it. There is an orange (high voltage) cable from the inverter to the compressor. To access the plug remove the black plastic shroud over the radiator. Have the car off and wear gloves while unplugging the compressor. Tape up the cable ends. If the code resets with the AC compressor line disconnected then the AC is not the source of the leak.

Get the codes read! This is like working with your eyes closed.

Brad

 

My Gen I had the P3009 code. I cleared the code to start the test. That was two years ago and the code has not yet come back. Weird stuff happens.

If you have the drivers door open with the car in drive the dash will light up with every light possible and dire warnings of impending doom. It says everything except "Shut your door dummy".

A MIni VCI cable ($25) and an old XP laptop is a good investment. Then you can read the codes when they happen.

Brad

 

Nitpicky, but the picture of the MFD in the OP is not an '05. It's an '06 or newer since it has the higher resolution UI style. Sorry about your troubles, but at least the car is newer than you thought?

 

That is a high voltage ground fault. Subside 526 does not narrow down the issue any further than the entire high voltage system.

Toyota thinks a high voltage ground fault is a safety issue, hence the car doesn't start after the code is logged. As your title shows you have already figured out - you can drive the car by first disconnecting the 12V battery for a minute to clear the logged DTC.

 

Same as what Patrick said. Along with the 526 there should be a 612, 613, or 614 code. They help to pinpoint the source of the leak. Here's a really good explanation of this.

2004-2008 Toyota Prius with code P3009 or P0AA6 and info code 526, 613, 614 | TOYO Headquarters

Brad