Big Red Triangle

My car (2006 Prius with 250k miles) was operating normally all day today. Still getting very good mileage around 52 mpg on average. Then abruptly, the big red triangle and few other yellow warning lights (check engine, VSC, and an indicator with exclamation mark in the middle) showed up while the car was moving around 20 mph. Now, the car does not have much power and it was very difficult to speed up or going uphill. Turned the engine off and then back on. The symptoms still persist. The battery indicator was at only 1 bar. Let the engine run for a while and the battery indicator went to 3 or 4 bars. Turned the car off and then back on, the battery indicator went back to 1 bar immediately. Also the battery fan was running at high speed, even through I have just started driving for about 5 minutes. Will do the following tomorrow: (1) check 12v battery, (2) use Torque SW to see if HV battery has proper values, and (3) read diagnostic codes. Please help. All suggestions are welcome.

 

Here are the codes: P0A80, P3016, and P3017. Most of the module pairs have resistance of .021 to .023, except module pair 5 has resistance of .028 Ohms. Voltages of all module pairs are 17.0v. Checked 12v battery which is fine.

 

Did not like the HV battery failure mode last night, which gave no warning prior to failure, except that I know the battery is 10 yrs old. Drove the car in limp mode for about 20 miles to Longo Toyota dealer for HV battery replacement. It is going to cost $3522 which includes the replacement battery G9510-47031, 5 hrs of labor, and tax.

 

Final cost is $3447.19 w/ one year warranty. The dealer also offered further $300 reduction for a (Toyota?) reman battery, but I declined. Perhaps my MPG, especially city driving, may now improve slightly with the new battery.

 

I have asked two dealer personnel from two different dealers, both quoted 1 yr warranty. Is the replacement HV battery warranty info online somewhere? Indeed, it is a lot of money for a 10 yr old 255k miles car. However, my car is currently in excellent condition without any other issue whatsoever.

 

Did not know anything about the Longo coupons and AAA discount. Got 15% discount on the battery listed price with some other minor $50 cost reductions. After all that, the total cost basically independently matches the quoted cost of $3449.65 from Toyota of Hollywood.

 

There was no warning sign to me at the time probably due to the fact that the HV battery deterioration was very gradual over the 10 year period. The state of charge bars were never fluctuating quickly. I was still getting around 53 MPG.

When the big red triangle abruptly showed up, I could only drive about 20 MPH max on a flat road, and was having great difficultly even on very slightly inclined roads that you might not have even noticed during a normal driving. However, I did have to climb a very short steep hill at around 5 MPH.

After the repair, I do notice some differences. The state of charge bars tend to stay in the middle blue section a lot more consistently. The engine does not come on as often as it did especially during the city driving.