Should my battery get this low?

That's normal, but I thought two bars would be red. On another note, when my car sits all day it commonly has one bar when I start it again. Is that normal, for it to lose several bars just from sitting for 9-10 hours?

Regards,
Dave

 

You have to keep in mind that the SOC meter is not a true representation of the battery charge. Empty is around 40%, all full is around 80%.

The Prius manages the battery SOC between this narrow range to ensure very long battery life. Of course, I'm referring to the NiMH traction battery, not the little auxiliary 12 vdc battery

The only time I've seen the battery gauge completely green - full - is in temps of -30 F to -40 F when the gas motor runs constantly in traffic.

Your battery gauge behavior is normal

 

Mine goes to green everyday, as I coast done long offramps and brake at the stoplight below. Then the battery spins off extra energy through the engine.

 

The first two bars are purple. The OP must have been mistaken.

Tom

 

You don't have to look closely. The first two bars are purple (magenta). All of the middle bars are blue. The top few bars are green. The colors don't supply any additional information, but they do make it easy to see the extremes at a glance.

The bar devisions are non-linear and have hysteresis, so don't get too worked up about exact numbers. It's just a guide.

Tom

 

No, definitely not. It sounds like you're not turning the car off properly - with the smart key it does not switch itself off when you get out. You must press the Power button to switch off - check that the READY light and the LED on the Power button turn off. With the key fob in the slot, there's a small solenoid that prevents you removing the fob if the car is still on.

With the car truly off, the HV battery is isolated from the inverter, motors and DC/DC converter. Any discharging is solely due to the internal resistance of the battery (termed self-discharge) and the car can be left for a few weeks without difficulty.

If the battery is self-discharging in less than a day and the car is definitely off, get the dealer to check it out.

 

Hi All,

Its common to get down into the third blue bar in metropolitan freeway driving with the AC on.

Are you running the AC down around 70 F setting in 85 F weather in slow and go traffic. That would be one scenario that would explain your experience.

 

Thanks for your input,

I am using the smart key, and I always push the power button when I stop. I wonder if this is an indication of my battery getting old? I have never driven another Prius, and I've only had mine for a couple of weeks, so I don't really know what normal is. I am getting good gas mileage though, about 46mpgs. The car has limited power for a couple of minutes when I haven't driven in 8 or more hours. After a couple minutes, the battery has a few bars on it, and the power is at a normal level. Is it unusual to have low power like that?

Regards,
Dave

 

The "limited power" warmup stage is a documented stage (see 5 stages of prius operation). This is where the engine focuses purely on warming up the catalyst converter and thus does not provide much power to drive the wheels.

 

Dave, your 2006 is NOT OLD and your battery is not acting normally. The only time I've seen this is when the slacking valet leaves the car on when parked all day. Nothing personal, but let's start with the basics. When the car is turned off the MFD is off, the instrument panel is dark, and the headlights are off. Lock the car by pressing the button on the outside driver's door handle. If it locks, everything is closed. If it beeps something isn't quite closed (most likely the hatch). If you are sure everything is off and you still lose battery bars when parked overnight then go to the dealer as the battery is under warranty.

[I know interior lights will only discharge the 12V battery but it is best to check everything.]

Your "low power" experience is the ICE running to primarily recharge the battery. This is normal. Sitting in traffic long enough with the AC running will draw down the battery.

 

My Prius is actually a 2004 with 162,000 so it is out of warranty. The car does beep when I push the outside button to lock the door, but I thought it was just telling me the alarm was arming or something like that. The beep is short though, I thought a long beep meant there was a problem? To be clear, let's say I park and there are 4 bars on the battery display. If I get in the car in ther morning there should still be 4 bars right?

Thank you,
Dave

 

No.

Yes, I am also starting to see 8 green bars frequently on my commute, dropping from 1,100 ft elevation to sealevel, and am worried that this is an initial sign showing battery capacity loss.

Upon cold startup, the gasoline engine timing is retarded so any required power is primarily being provided by the traction battery. If the battery has low capacity, then this would explain the limited power that you notice. The mpg indicates that whatever might be wrong is not dramatically impacting drivetrain efficiency.

A short beep accompanied by the doors locking is normal.

Yes, in general if you see 4 bars when you make the car IG-OFF then the next time you make the car READY you should see the same reading.

 

I usually see two red bars only when running the air conditioning while the car is READY and stopped for a while. I agree that it is unusual to see such a low traction battery SOC reading after driving on the freeway at 65+ mph for an extended period. However if your car doesn't have any warning lights on I doubt that the dealer tech will be able to do much for you.

 

Thanks Patrick,

It sounds like my battery just doesn't have the same capacity as a new battery. I guess we'll see how long it lasts. I'll keep it as long as I'm getting goog mpgs. I appreciate your input.

Regards,
Dave

 

Sounds like you might have the corroded traction battery connection issue. Search around here for it as there's lots of discussion's about it. In the meantime the other sore spot on this high mile Prius you might need to address is the transmission fluid. Even though it may be a "Certified Used " car I highly recommend changing that fluid out. Its really pretty cheap and not very hard to do yourself and may save you a CVT transmission. It uses approx. 4 quarts of WS Fluid found at the dealer.All you need to do to make a Prius happy is keep after the fluids.Good Luck.

 

Thank you,

I will look into the corrosion issue. This is not a certified car by any means. I will replace the transmission fluid, but I need to fix the oil pan leak first. I already replaced the HIDs and the remote battery.

Regards,
Dave

 

I'd be concerned about the losing several bars overnight...

While driving it, does your car lose or gain several bars within a few minutes at random?