2008 hybrid battery drains overnight

That warning light is not the flat tire symbol. It's a different warning

Your battery is getting weaker but it's normal operation in the morning for it to dip more on a weaker battery.

 

Very normal to drop a bar or two. Sometimes even more with heavy A/C use, BUT if this is new behavior, it is likely sign of a failing battery.

I recommend you conduct the discharge test linked in my signature to assess your battery health.

That is normal at a low state of charge with heavy A/C use or extended sitting with the ICE off. The car force-charges the battery and refuses to use the battery for propulsion.

Battling a slow leak for months? How do you do that? Take it to a tire shop. If they can't repair it, replace it. Battle over.

I can't imagine that condition contributed to the range or battery issue unless it also contributed to reduced mileage. The Gen2 has a fuel bladder, so the amount you fill up is somewhat random depending on how stretchy the bladder is that day.

Again, I recommend you conduct the discharge test EXACTLY as described in the link in my signature. It will give a good approximation of the state of your battery.

Steve

 

Your car is exhibiting the same symptoms as my bought new 2007 at 95K miles. You didn't mention where you live but I bet its a warm climate like me. Cabin heat is a battery killer.

Your battery is showing its age. You have an excellent option available to you though. Since the car has not thrown a Hybrid DTC none of the battery modules have thrown a hard failure yet but thats coming eventually so it is an excellent candidate for a Hybrid battery Charger which will extend the life and rejuvenate that tired battery. I bought mine a few months aback and plan on using it this weekend. They work.
The cars software does not allow the Hybrid Battery to be 100% charged due mainly to the heat it generates. The charger is outside the cars software so you can achieve a 100% charge under controlled and cooled conditions.
The company that sells the charger is seeing great results on this site. They are sponsored on this site.

Hybrid Automotive.com

Btw, the light you are seeing is the Tire Pressure sensor and its not because the tire is flat usually at your age but the battery of the sensor itself has died. Battery's in these last about 7-9 years. The battery is integral to the little sensor. Its kinda expensive to replace the sensor as after replacement you have to go into the techstream software and install the sensor new serial number for the car to see it. Unless you have a mini vci that's a dealer deal.
Sensors are $50 each on amazon.com plus tire install each tire plus dealer charge to fix the serial listing in the software.

And your mileage is tanking because you have alot less hybrid battery assist. Its all motor now. The fact that the car is unhappy enough that its having drivibility issues tells me the hybrid battery is getting ready to throw a hard failure. Mine drives ok...mileage is getting bad and the battery goes empty much quicker.
Cabin heat. Especially if you don't use the ac. I use the ac every second but man its hot down here.

 

(!) Is not related to tires, there is a different warning light that looks similar for tires, not with the exclamation

 

If the discharge test suggests deteriorated capacity, I would recommend the HA reconditioning system.

 

Thanks guys for the recommendations. Pro-289, your battery sounds like an ideal candidate for our products. We have had scores of Prius owners in your exact situation benefit from our products. You can read more about them here:
Prolong Grid Charger FAQ - Hybrid Automotive

Feel free to give us a call at 800-589-0730 if you would like to discuss your options.


Jeff

 

that's a lot problems for a one owner 2008 w/ 107k. does it see heavy usage?

 

do you live in the boston area?

 

the one in the priuschat shoppe should be correct.

 

Sure, happy to help, the Prolong Battery Reconditioning Package has everything needed to easily recondition your hybrid battery at home. This package is ideal for people who have already degraded hybrid batteries, or batteries that are showing a fault (DTC) code.
Prolong™ Battery Reconditioning Package - Hybrid Automotive

The Prolong 'Discharge Ready' Battery Charger is recommended for batteries that are beginning to show signs of deterioration. This version of our systems are compatible with the Prolong Battery Dischargers. Many of our customers opt to perform in-car battery reconditioning as their batteries age, which requires both a charger and a discharger. The Discharge Ready option allows for easy 'Plug-and-play' addition of a Prolong Discharger later.
Prolong™ 'Discharge Ready' Battery Charger - Hybrid Automotive

The Prolong 'Standard' Battery Charger Package is designed to be used as preventative maintenance for healthy hybrid batteries. The Standard package allows for charging and balancing of the hybrid battery, but does not support battery reconditioning (deep discharging of the battery). By occasionally using the Standard charger system as preventative maintenance, battery degradation can be significantly delayed and often eliminated for the service life of the vehicle.
Prolong™ 'Standard' Battery Charger - Hybrid Automotive

You are welcome to build you own discharger. We have customers who buy just the plug with leads from us often. Feel free to give us a call if interested 800-589-0730 in this option.

 

It is not a bug, it is by design. If you wait a bit longer (with the HVAC off) for the ICE to stop (should take 55 sec with the battery on 6 bars) before driving off, you will find the engine runs smoother (unless you have other engine issues).

See the "Hybrid Warm up: 5 modes of Prius Operation." link in my sig for a better understanding of what is happening.

What you are experiencing is the Prius still in stage 1 and in this stage primary propulsion is via the electric motor, once the warm up progresses to stage 2 the ICE reconfigures to take over driving duties. When your HV battery is in a poor condition, stage 1 takes a heavy toll. If you can wait for stage 2, it is much more gentle on the HV battery, as you have experienced also. (Caveat: if you press the go pedal to the floor in stage 1, all bets are off and the Prius reconfigures for power and skips straight to stage 2. There is a slight hesitation while it does this.)

 

Ditto the above.

It sounds like you have a minor engine issue, maybe a tune-up item. Have you ever cleaned the MAF sensor? Also check and clean the throttle body. The plugs and PCV valve are probably original, you might want to change them. Maybe some injector cleaner. Basic tuneup stuff for a modern engine, not bad for 100K+ miles.

It's tempting to think such an advanced electronic system is all controlled by programming, but there's still an internal combustion engine in there with parts that get dirty and wear out.