Diagnostic Trouble Codes P0K92 and P0K7K

I have diagnostic trouble codes P0K92 and P0K7K set on my 2008 Gen. II Prius. I have searched the forums and cannot locate these two codes.

I started and drove my car for several miles today, then it started to run rough. I pulled over, then called a tow truck to tow my car back home. I have a high-level scanner/code reader that read P0K92 and P0K7K codes.

I have also searched for a list of trouble codes, but have not found a list for my application.

The car now starts, yet has only two purple bars on traction battery. 12VDC battery is tested within specs for no-load and load conditions. Please advise. Thanks!

*** UPDATE ***

The car starts, the check engine light is on, the red triangle light is on, MFD has a small red car icon with a "!" in the middle of it (in the upper-left of MFD), the accelerator pedal does not seem to increase the engine RPM speed.

 

Patrick:

Thank for the info regarding the Mini VCI scanner. I'm not surprised that my cheap scanner is showing bogus codes for my Prius.

I'm unable to photograph my display and post at this time.

Car starts OK, but MFD does not indicate any power transfer to/from motor to battery. A/C does work OK.
MFD has a "red car icon" with "!" in the middle of it, which is present in upper-left of MFD screen.

"VSC" light is (was) ON on the dash too...

However, I just went out to start the car and re-observe the indications/icons.

a. Red triangle is ON.
b. "Check" engine is ON.
c. MFD has a "red car icon" with "!" in the middle of it, which is present in upper-left of MFD screen.
Now, the MFD 'DOES' indicate that charge is going into the battery (This was NOT the case an hour ago) - it showed NO CHARGE path indications on the MFD at all. Hmmm...

 

Thanks for the replies...

Q: Whats the miles and is this car new to you and does it have a salvage title?

A: No salvage title. I am original owner since new. Car has 186,xxx miles. New Exide auxiliary battery reads at proper specs (It's new installation did not resolve any of my recent problems with the car.)

Q: Has your car had the TSB done to replace the Inverter Coolant pump?

A: Yes...The inverter pump was replaced within a year ago. Inverter coolant reservoir does have agitation within, suggesting that the inverter's coolant pump is working OK.)

Q: Do you see violent agitation in the Inverter Coolant tank when the car is in ready? If not the coolant pump has failed and severely overheated the Inverter. (See above answer).

I ordered a "Mini VCI" code reader, but it has not arrived yet... My cheap code reader indicates that codes are present, yet reads them as non-standard Prius codes (Note the two codes cited in the title of this thread's OP.)

As of this morning, I tried to run the car for awhile to 'charge' the HV battery. The HV battery initially showed 4 blue bars, and the Information display showed charge going from MOTOR to BATTERY. Then, after a couple of minutes, the charge flow indicator did not show any charge flow to from MOTOR to BATTERY. ALL charge flows were blank (not indicating anything charging. RED TRIANGLE is ON, and MFD has RED vehicle icon with "!" in upper-left of display. "CHECK [engine]" light is ON. "VSC" is illuminated.

Given that I do not have a proper 'code reader' for the Prius, I will attempt to seek one out here in the Portland, Oregon area.

Any additional input is greatly appreciated. Many THANKS to those who have positively commented so far~

 

Should a person be able to hear the HV Battery cooling fan ON at all times, or after a certain run time/temperature? Please advise.

I verified that Trouble Code "P0A92" (Hybrid Generator Performance) is the code that continues to set on my car... I used a 'borrowed' OBDII code analyzer to observe/clear/re-observe. This same code re-apperared after clearing the previous P0A92 code.

 

Many thanks to all who have weighed-in to help me resolve my Prius issues. Good advice from all.

I received a "Mini VCI" diagnostic USB-powered scanner tool today. I read the trouble codes that have been set on my car with this device.
Trouble code P0A7A (Generator Inverter Performance) had been set. I cleared the code, ran the car in my driveway for a time, then the same P0A7A code set once again. Inverter? MG1? Thanks to the previous poster regarding the checking of MG1 windings. My Inverter water pump and coolant has been changed under factory recall within the past year. I do see "turbulence" within the inverter's coolant tank.

My car is mostly a daily driver, and I have smelled no "burning smell" to date. I resonate with Ed's previous comment regarding low voltage/high current on windings. Sadly, the tranny fluid has not been well maintained, and may have been a factor with my current issue. The Prius has been otherwise fault-free over the past 186,000 miles. I did use the diagnostic tool to observe the HV Battery voltages and resistance readings - the voltages all read to be quite equal. I'm still getting use to the Mini VCI software's user interface.

I do not have a milliohm meter. I do have a DVM that *may* be able to measure resistance down to < o.109 ohm. However, I do not know where to access the stator winding 'ends.' @Patrick: Can you expand on this for me..as to where I may access the windings to be measured?

May my issue be a failed inverter? What may be the odds in favor of inverter failure over MG1 failure? I am a newbie at diagnosing Prius issues, but am an experienced (and GM-certified) shade-tree mechanic. Thanks to all for your input and your patience! Greatly appreciated here...

 

@patrick:
Code P0A7A (with sub-code 325) has set, and was read by my new-to-me "Mini VCI" code scanner.
Thank you for the tip regarding techinfo.toyota.com - I will subscribe, read, and learn more about the procedure to measure MG1 my windings.
__________
Other sub codes that set *once* (a day or two ago) were:
C1310 (ABS/VSC/TRAC)
B1421 (A/C)
These two codes set only *one time*, were cleared, and have not returned to date. Do these two additional codes yield any clarification to my car's problem?

I understand varnish-type motor winding insulation burning/melting together/shorting windings, etc. due to shorts, high-temps, and/or high current. In a previous life, I have had electric motor windings dipped and baked with special insulating varnish at specialty motor shops. I have not (yet) removed/replaced my transmission fluid - or sampled it for color/smell.

Any additional insights regarding the three subcodes mentioned above?

 

I rechecked my trouble codes today:

P0A7A/325 and P0A92/261 are set (current and historically.


I'm using a Mini VCI scanner connected to a Win XP laptop.

The Mini VCI tech software also indicates that the CAN bus is not communicating.

My 2008 Gen II Prius 'readys', starts, runs, and idles. The MFD displays a charging path from ICE to HV battery OK. The A/C comes on and works OK.

However, if I press the accelerator pedal, the ICE speed RPM increases, THEN the RED BANG TRIANGLE appears, sets the trouble codes above, and there is a) no more response from the accelerator pedal, and b) no charge path indication on the MFD (like there was before). Pressing the accelerator pedal does nothing after the trouble code sets. However, after shutting-down the car, re-readying, I do see MFD charge path from ICE to HV Battery again...then when I press the accelerator again, the ICE stops accelerating, and the charge path disappears.

Any thoughts about this? Bad/loose connector(s), wiring harness? Thanks in advance...

 

@ Patrick: I'm hoping no, but... I need to get under the car and check the harness connectors too.