Good morning everyone. I have a 2005 Prius with 124,000 miles. I've owned the car for 6 months and its been great. Regularly get about 50mpg. All of a sudden however, (within about 3 days), the state of charge has seemed odd. Usually has always stayed between all blue bars and one green bar because I drive mostly highway. However the last few days when I leave the house in the mornings, it seemed to use more bars to get going than usual. Once I was on the road all was good and it charged back and held the charge. Well this morning I left the house and it actually seemed perfectly normal. I drive 50 miles one way to work and as I pulled into my parking garage (all blue bars), it drained all the way down to purple in the span of about 15 seconds for me to get to the 4th floor of my parking garage. I knew that was odd so I went back out and drove around a bit and came back and all seemed pretty normal. Then as I got to the third floor coming back up, the red triangle came on and said there was a problem. The battery had drained again. I shut the care off and turned it back on and the triangle was there but the engine was charging the battery. I watched it fill all the way to 4-5 bars. What's going on? I have read on here and talked to shops and generally a Prius starts to exhibit signs such as random SOC swings and poor MPG when the battery goes. They never seem to just go. Any ideas?
Have you heard the cooling fan (in the back seat grille) yet? That's another sign. I agree, it sounds like a hybrid battery problem. I believe that when the red triangle comes on, there's a diagnostic test code recorded. A Toyota scanner would be able to pinpoint the problem. Without that code, we're guessing. Choices are to pay Toyota for diagnosis (usually around $100), or purchase a compatible scanner like the Mini-VCI, about $20 plus an old (32-bit Win7 or XP) laptop.
I don't believe I have heard the fan. To be honest I wouldn't know what it sounds like though as I'm not sure I've ever heard it.
Torque pro makes a cool. Android app that works with a module you can buy for cheap that tells you codes and even assist in looking them up. But yea, your traction battery is failing it sounds. When it acts like a small battery that's easily & quickly drained and quickly charged is a good clue. Based on what part of the country your in there are folks that can bring you a refurbished right to your home and be done in one hour with a year/25k mile guarantee for about 1000.00 or so for 2004 - 2009 & about 1400.00 for later. I've done it twice now no problems since. I'm in Texas area, I used home town hybrid. Services | Hometown Hybrids Here is a map of mobile services in my area. SM-N910V ?
I've called around to some Hybrid shops and they're all at least 30 miles away. Two of them quoted 2200 for a refurb install. One is at 1500, which still seems high to me. I've watched a few videos and it looks like a piece of cake install, so I'm thinking of buying one off ebay and installing it myself.
The install of a HV battery is fairly straight forward for someone with reasonable mechanical skills and an understanding of the what you are doing. Just be mindful of used or remanned batteries as it is the proverbial game of "whack of mole" as HV cells continue to reach their effective life cycles.
Keep in mind the age of what you'll buy from salvage. It may be a functioning battery, like yours was until recently, but it's still going to be ten years old, plus or minus. Ten years is a good shelf life for any chemical battery, no matter how much use its gotten and how well it's been stored. It still may be a good option, but you know there's always a downside, and it's a bit of a gamble. With reasonable skill and care, the installation is simple. For me, the riskiest part of it is back strain. It's not that heavy, around 80-90 pounds, but there's no way to lift it in a good position. I recommend getting a second back to help on the lift.
I understand there being potential downside of a used battery but a re-manufactured one from a reputable source should hold up well shouldn't it?
Depends on your definition of reputable. The 'Dorman' product comes with a 3yr unlimited mile warranty.
Dorman is the one I'm looking at. I'm just so disgusted with this whole thing. My car had none of the warning signs of a bad battery. I drove it 200 miles just yesterday and the battery held a perfect charge and functioned completely normal. It was even fine for all 52 miles of my commute this morning and didn't act up until I got ready to park.
I believe your battery with only 124k miles on it will be better than most rebuilds that you buy. Those will normally have higher mileage on them. Maybe you can invest I a grid charger and possibly replace a module? That'll be way less expensive and you'll probably have a good battery and a charging system for use when needed SM-N900P ?
Good point about my battery. Last thing, Is there anything else that can be causing this erratic behavior before I go and pursue another battery? I don't have a code reader and I'm uneasy about going to an auto parts store to read it because I'm scared I'll get there and the car won't start back. Right now I just want to get it home.
I would first see what the code(s) are first before getting another hybrid battery. It quite possible that it is a hybrid battery issue but start with getting the code(s).
Could it be possible that this is something not as major as the HV battery? I went out to the car and started it, and it fired up fine with the battery at 3/4 full. Its like the car is fine other than the lights.
It is possible, but without reading the stored DTC (and INF) codes it would be hard to say with any certainty. It is also possible that with a few power cycles the lights will go off on their own, leaving just the logged codes for you to reference in the near future. If you plan on driving it home today try to refrain from high amperage usage (gunning it from a stop or pushing it on a steep hill). Also, If possible keep your top speed down, which of course can be difficult and unsafe on a highway.
When the battery is going bad it loses capacity, almost like someone stole your battery and replaced it with one much smaller. Result is it charges quick and drains quick. Starting at 3/4 is fine but how fast will it deplete forcing the ice to kick in? Often it will drain to purple quite easily if running on accessories with ice running "non-ready mode". All lead acid batteries recover a bit after sitting "unless there's an internal short", so it's not surprising to find it looking OK first thing in the morning but then it drains quickly. When you punch it from slow speeds the traction battery can't deliver the amperage so the car is sluggish without electric support. I'll be surprised if it's anything else. Your mileage is fine as it usually takes about 200 miles to get them but the years of use is your enemy. If you're going to try and get 300 + miles I would consider new, otherwise rebuilt should give you another 100k SM-N910V ?
