So I got bit yesterday - Red Triangle, CEL, Problem

I pull out of my apartment complex and the dashboard lights up like a Christmas tree. I've got red triangle, CEL, Problem with red car and ! on MFD, and for some weird reason I believe the brakes indicator--it looks like this ((O)) with an ! in the center.

That indicator has since gone away, but I still have the other three. Today, very first thing I do is pull codes. None, still showing all three indicators though. Checked the 12v battery charge state on the MFD and its showing 11.8 volts.

Whilst driving, I have noticed that the hybrid SOC has been very erratic, going to full in about 100ft of coasting to a stop light from -2 bars from full.

So...is my hybrid battery toast or is the 12v toast? I am prepared for the hybrid battery being toast. The Prius has allowed me to save enough money to have it replaced, so that isn't an issue. And I can replace the 12v battery easily enough.

This is all on my 2004 Prius with 125k on the clock.

 

Oh yeah, one thing I forgot to mention is that the 12v is an Optima Yellow top that is 1 year old. If it is toast, I guess time for a regular battery from the stealer.

 

Ok. So I pulled the 12v and measured at the terminals, and the reading was weird. Since I also purchased a replacement 12v Bosch branded battery from the auto parts store (anticipating a replacement) I measured that one at the terminals as well. Same reading: 15.5-16.0 volts.

With the battery now out, I turned the car on and of course codes cleared. Drove to the auto parts store to return the Bosch, bought some gas, came home. No codes in the 8 miles driven. Gonna check the voltage in 30 mins as per the owners manual to see what the 12v SoC is at.

BTW, don't buy the Bosch branded battery. It may be the same battery code and specification, but it is too big to fit in that tiny space with the battery holder in place.

EDIT: If it is the wheel speed sensor, would the codes be thrown again after being cleared?

 

UPDATE: Took the Prius to the dealer yesterday and they diagnosed the problem. Hybrid battery going bad AND inverter pump starting to fail. Price to fix is OMFG are you kidding?! I had an inkling that the battery was going bad because I've watched it for the week leading up to the DTCs being thrown and the battery was going to full in under 100ft of coasting.

Since I plan on keeping this car for a long time, I said eh do the repairs. Didn't even bat an eyelash. In the years I plan on keeping her, she will have saved me enough money on fuel costs alone to replenish my repair funds.

Now that my battery is new, I will be observing its behavior diligently to see how the vehicle acts with a new battery.

Oddly enough, when I was there yesterday, I asked the parts counter guy about the warranty on the battery--because I read somewhere on here that the warranty had been upped by Toyota from 1 year to 3 years starting in the new year--and he didn't know anything about it. I will ask the service rep guy when I pick her up today again.

dorunron: the battery trays are different sizes for with and without SKS? The Optima I have is specified for SKS because that's the only one that was listed at NAPA. Would explain why the Optima doesn't quite fit inside the tray because I have a non-SKS model.

Goldfinger: probably just need a new battery in the DVM. It is a Craftsman and I have had it for years now with the same battery. But, that is what the VDC reading was. I'll put a new battery in her and test again in the coming weekend. I need to dig out a couple of screws and put in an SKS battery tray so the battery will fit better.

 

Alright. So my first commute with the new battery in the Prius and here are my first observations:

- Car feels peppier going up hills. My commute involves about 3.5 miles of rolling hills (7 miles both ways). Whereas the ICE would kick in quite audibly to make it up the hills, with the new battery not so much.

- There is a 0.5 mile stretch of downgrade that I coast starting at 50 mph, bottoms out at about 38 mph, then starts accelerating because of a steeper grade hitting about 55 mph at the bottom. With the old battery, the charging starts at 8 blue bars and hits full bars at about 0.35 miles into the coast, forcing me to shift into B before coming off the hill. With the new battery, It barely charged up to 9 green bars when coming off the hill.

- Coming off the freeway, it's a 4.5 mile stretch of straight pavement with 6 lights to my apartment. At 1am in the morning, there are few cars so I usually cruise that stretch at 35 mph. With the old battery, possibly due to the colder months, the longest I've been able to stay in EV mode was about 1 mile before the ICE kicks in. Before the DTCs were thrown, this had dropped to as low as 0.3 miles--really bad. This was from 9 green bars, and, due to the condition of the battery, full bars a few times. With the new battery, I was able to cruise 1.3 miles before I had to stop at a light starting with 9 green bars. Coming to the stoplight, I had only dropped to 5 blue bars.

- SoC seemed more stable and consistent. With the old battery, when I first bought the Prius, I noticed what other people had noticed: when dropping bars, usually from 6->5->4, it was quicker than expected. Dropping from 7->6, stayed at 6 for about 20 seconds before going 6->5. Stayed at 5 for about 10 seconds before going 5->4. Sometimes it continued 4->3 before starting to go back up. With the new battery, since I've only seen 5 bars at the minimum, SoC stayed there much longer and didn't drop at all. Each bar seemed to last just as long regardless of how many bars there were to start. I will have to observe this again before I can comment further.

Now down to the nitty gritty:

- Brand new battery: $3938.67
- Core return: $1350
- Cost $2588.67
- Brand new inverter coolant pump: $128.38
- SLLC Coolant: $21.43
- Labor total for job: $1155.54 (bought evenly distributed between both parts)

Old battery had code P0A80 (replace hybrid battery). They also read a code (not listed) stating INVERTER COOLANT PUMP INOP.

The job to replace the battery alone was already at $3200-$3300. What really pushed it was the inverter coolant pump needing to be replaced as well. Oh well, better than needing a $4000 inverter.

Service Rep Guy maintains that battery warranty is still 1 year only and that he hasn't heard or read anything differently. He recommended that I call Toyota to find out.

If there are any observations that you guys would like for me to take on having the new battery, feel free to make a request here or PM me. Will gladly look into it. Just keep in mind that I will only be able to make extensive/detailed observations on Sundays and Mondays, the days I have off from work. I'll probably dig up this thread again when Spring/Summer comes along and battery capacity returns to normal and make more observations.

 

Buried in the paperwork was this tidbit about the hybrid battery:

Performed further inspection and found the battery block V13 shows only 13.08 volts all others are at 14 volts.

I am a DIYer, I like to do maintenance myself. But since I moved out of my house and into an apartment, I'm no longer able to do even a simple oil change.