2005 Prius Diagnostic codes P3190 and P0171

This is all theory as I try to troubleshoot my Prius problem. I read an interesting article
and if true it sounds like I drained my 12 volt battery briefly while I was running both front, back electric defrosters and running a plug in defroster to defrost the windows because I never got my cabin blower fan repaired. This could have triggered the Engine control module to go back to default setting for the gas throttle valve which is to barely have the valve open at all.

This would explain why despite repeated attempts at accelerating I found I couldn't get the electric engine to switch over to gas and could only go about 30mph. The gas engine was running but was not recharging the main traction battery and eventually the car stalled to protect the battery from going below it's point of no return (I wanna say 50% or something like that).

I had my Prius towed and got a code reader to troubleshoot which gave me the codes P3190 and P0171 which are poor gas engine power and fuel system to lean. It seems plausible considering my 12 volt is 4 years old (refurbished Optima deep cycle) and I didn't get the dreaded P0A80 code signaling a defective traction battery so I'm hoping I didn't drain it too badly despite repeated attempts at trying to start it.

My Question now is, does anybody know of a way that I can reprogram the ECM so it will allow my gas throttle to work again and thus recharge my main traction battery? I hate to have to bring it in to a mechanic so they can figure out the most expensive way to fix this little problem.

 

Yes. That's the article. The code reader is an Inova 3100. Haven't tried cleaning the throttle body yet. Last night dumped another 3" of snow and it's parked out on the street. Snow will hopefully be gone tomorrow. I just don't think it's a coincidence that I have this throttle problem after putting so much stress on the 12 volt. But I probably should check the MAF and TPS first.

 

Verified this morning. Correct.

 

I've got 176,000 miles on her. And thank you for the codes pashko90. Have no idea why these codes popped up and here is why.

Today I took it in to the dealership to get diagnostics run on it. They call me back around noon and say they can't run any codes because the 12 volt is completely dead. So they want to move forward and replace it and charge me $470 for a battery before they can do anything else. I tell them don't touch anything and I'll get my car. I stop to Autozone on the way and pick up a replacement Optima battery for $185 and get the people at the dealership to roll out the prius in the parking lot (they won't let me work on it behind the fenced area) and I put the battery in the car. I proceed to try starting the care and it starts just fine. I drive it around a bit to get the main battery charged and park it back at the dealership.

There is a simple way to test your prius 12v by using the self diagnostics on the prius menu. 1) press power button without touching brake pedal 2) hold down on the display button on the monitor while turning your headlights on and off 3 times. 3) let go of the display button and you enter the diagnostic screen where it will show you the 12v charge. When I saw 11.5 that number should have raised my suspicions that the battery was bad.

I could have kicked myself when I realized my mistake. On the plus side, when they examined the car they noticed a leak with the water pump that is dripping fluid on the radiator belt. But was that worth $118? Probably not. I drove it home and am keeping it in the garage from now on.