Long explanation to my question. This afternoon I was making 160mile round trip drive. About half way back 40-45 miles I went to stop to grab a coffee. Up until then everything was perfect. Put on the directional and slowed to turn in to the parking lot and suddenly “check hybrid system “ came up and the car lost all power and I rolled to a parking spot. I shut it down and took a minute , then restarted and went for it to see if it would drive or I was dead in the water. I was lucky (I guess) and it drove. Check hybrid still on as well as triangle ! Light, quote ! Light , traction light, and check engine light. The car accelerated like it was a manual transmission with a bad clutch and also stuck in 1st. But slowly climbed up to speed. It always felt light it was reved up about but the mpg fluctuated like normal 100mpg down to 20 based on my acceleration. I was able to drive the remaining 45 miles home at 70 mph highway speeds and consistent back road speed…with the exception of the slip clutch feel and the higher rpm’s it ran without a problem to get home luckily. When I got home I ran the codes. POS90, P0A94, both control unit 7EA. Also codes C1259 and C1310. I looked them up and it vaguely points to an inverter but also other things including low or bad 12v battery. Added: I alway manually shut off my head lights even though I see they will shut down on their own. But today I forgot. could that have worn down an old possibly weak 12v battery enough to after 40 miles set my chain of events? Also, I’ll add, a few minutes prior to this I turned on my heat also. Wondering if the heater fan load on the battery triggered a drop in a battery on the edge of low volts to drop enough to trigger my coated and events. I’m hoping someone has some insights and explanations to rule out my thoughts or validate. Tomorrow I’ll test the voltage, but for now looking for some info and prying it’s just an old battery issue. I’ll also note: my daily commute is one mile each way with headlights in the am. I’ll go months without driving more then the commute and or a few miles around town. I’m wondering if I’m killing the 12v by not giving enough driving time to maintain voltage. thank you for any help and insights. 2010 model.
I just ran scan tool. Foxwell. I snapped a few pictures of what the batteries were doing( I guessing that’s what he graph represent) the first is just starting the scan and the car on but not running. The dip in voltage is where I turn on the headlights. I’m not sure on the charge percentage for the hybrid bat, I’m not sure how that works…if it goes up or down based on charge. And finally the volts (2nd pic). The other pic is with the engine running and the 12v jumps to the 14.8 but the charge percentage begins to drop. I went for a quick drive and all the drive problems from my post are still there. The hybrid charge percentage did go , and stay , around 40%. I’m curious and hoping the now voltage and with the load lower it more indicates the 22v battery is causing the problem (HOPING) but it seems odd that when running I was getting the 14.8v …or is that because it’s drawing back from the hybrid battery ( I thought I read that somewhere) Again. I appreciate any help, thoughts. I can not get sub codes only the PO’s.
I just did these next three screenshots. The one that shows 11.9v with a drop is with car on but not running and I turned on the lights. the jump to 14.8 is when I turned on the engine. And the steady(sort of) 14.8v is as it’s running. I noticed a slight drop in the hybrid battery when the engine was running and the 12v was reading its 14.8v. Any ideas?
Sorry. Last part I need to add. On the drive and at idle it never switched to electric. Usually if I’m sitting at a light or whatnot it will switch to electric only. Also, other then all the warning lights and continuous engine running it seems normal EXCEPT the slipping at acceleration.
C1259 and C1310, as you can read here, are just codes set by the brake/skid ECU when it has received news of codes in the power management control ECU. Those, of course, are your P0A90 and P0A94 codes. Given that the P0A94 code should qualify you for coverage under Customer Confidence Program 23TE03 as you can read about here, I would suggest contacting a dealer promptly (without clearing the codes) so they can sort it out.
Wow, thank you! I’ll give my dealer a call tomorrow. I bought my Prius used 2 years ago from a Toyota dealer , so I definitely be inquiring to them. I appreciate your help. So, would the P0A94 fall under a warranty coverage?
Yes, it is covered under a 20-year extended warranty. The repair will be covered 100% by Toyota, so make sure you do not clear the trouble code.
Cham thank you for this. I bought my 2010 from a dealer 2 years ago. I will reach out to them tomorrow…Also, closer to me is the actual dealer that sold the car when it was new. They are in my town. I saved the bulletin and have not cleared the codes. thank you again. edit: sorry about the repeat reply. I didn’t see my first had posted. I wanted to be sure you got my thanks for the info. Very appreciated!
