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Discussion Starter #1
I have been noticing that the energy monitor bars on the dash screen are starting to fluctuate rather quickly; i can go from 1 green bar down to 2 pink bars in a matter of 10 minutes driving (usually in town, but a couple times on long distance trips). Do any of you have the same situation? Or i will park the car with 5 or 6 blue bars showing, and when i start up the car an hour later or so, it has gone down to 2 pink bars. At one point on a trip up the mountains (a one time occurance as i live in the flat desert), i got down to only one pink bar. But the car always replenishes back to blue and sometimes to green. Have any of you experienced this?
 

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If you are using the A/C, which I'm sure you are in Palm Springs, this is normal. The A/C with the compressor running full bore will deplete the battery down to 1 or 2 bars in a matter of minutes. This is especially noticeable when first starting out (when the compressor has to work the hardest), and in town when you sit at lights and the A/C runs without the engine on.
 

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I'm with redwein. We just had our hottest day of the year. It got up to 34 C yesterday! Well, that's hot for here. ;) I hear Vegas was at 50 C. Ouch!

Anyway, I noticed my battery was fluctuating more than normal as well, and my car is new. It's probably the A/C. I don't usually use it but it was working fine yesterday. Oh, and I heard the rad. fan for the first time yesterday as well. ;) The coolant actually got over 80 C. I saw 87 C once.
 

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It sounds weird to me - I occasionally get rapid fluctations like that, but only when driving in the mountains, not on level terrain. And I've never heard of the battery state changing like that when the car was not running. You should consider having it checked out.
 

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Anybody who lives in a hot climate will tell you this is what they see when they run the A/C. It can drop from nearly full to 1 or 2 bars while waiting at the first stoplight going home from work for me. He is in Palm Springs which is extremely hot right now so it would be unusual if it didn't happen. I'm guessing the battery state doesn't change so much while it isn't running. It just goes down very quickly if the battery is left out in the sun to bake and you turn the car with the A/C on.

I believe the charge state isn't linear per bar and that the middle bars show charging and discharging more rapidly than the bottom 2 and top 2. That's what can be deceiving and make it appear that it discharges while sitting.
 

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It's the A/C. I commute about 160 miles daily in So Cal and I drive close enough to the coast that you rarely need A/C. This week was different. Was driving 20 miles without A/C and was in the green bars and had to flip the A/C on and within 60 sec was half-way down in the blue. With the A/C on it never was green again- always blue. When It started to cool down later into the trip and I turned off the A/C the green bars were back within about 60 sec.
 

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Coolant temp ?

I am in Largo Florida and have the same experience, my A/C is always on.
David Beale wrote "The coolant actually got over 80 C. I saw 87 C once." Dave, where do you see the coolant temp registered ?
I have a 07 pack #2 and see no coolant temp on mine dash board.

Thanks,
Terry
 

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Just taking my on a short trip to lunch and then getting around a few traffic stops to get on the highway and I come down to 2 bars. Seemed soon to me, but the AC was working hard.

It's normal if it is occuring at stops or very slow travel.
 

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DanMan32 said:
It's normal if it is occuring at stops or very slow travel.
Yes, but note the original message:
Or i will park the car with 5 or 6 blue bars showing, and when i start up the car an hour later or so, it has gone down to 2 pink bars.
That's not at all normal. ... Unless, of course, he's forgetting to turn the car off, which is possible. :wink:
 

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Like I said, I have tricked myself into thinking that too since it goes down so fast when starting the car. It "appears" that it dropped sitting there,. In reality, I backed out of my parking space and started heading out the parking lot, then looked at the display. In that time, it can drop and it gives the illusion that I mentioned. Remember, people don't always remember every detail exactly. That's why eyewitness testimony is less ideal than forensic evidence.

When you take his whole description into account, it is most likely normal. That is more likely than the coincidence of the exact behavior expected in the heat with an abnormal behavior that adds one slight kink into it but matches it otherwise perfectly.
 

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Besides, do we know the parameters Toyota used to calculate battery state of charge? I doubt it. Remember, the battery voltage varies by state of charge and the inverse of temperature. It could be a nice hot battery indicates differently than a nice cool one.

I've read that the SOC meter may rely on the computer's calculation of charge in minus charge out. This would be a good way to go, but not totally accurate. So the system may also use battery voltage to help correct errors that creep in from the calculation. In extreme situations, such as 50 C days, this could cause indication errors.
 

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Maybe somebody can comment in a more quantitative way about this, but battery efficiency is significantly affected by vehicle cabin temperatures. A very hot battery won't charge or discharge like a batter running at optimum temperature. This may have an effect on what is reported to the MFD, highly sanitized as that information is.
 

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And it has been extremely hot in Palm Springs recently. The 10 day forecast shows highs 105-114 which will really make the A/C work hard and consume a large amount of energy.
 

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Discussion Starter #18
redwein is right. I didn't keep my eyes on the screen as i was backing out of the garage or the parking space. I only noticed that it was blue when i started the car. a FEW MOMENTS LATER i noticed the pink. By the way, this was all happening with outside temps in palm springs between 110 and 117. Yesterday I drove to LA, and i saw green (especially coming down out of the hills), but iit never went to pink. It was mostly 4 to 5 blue bars, and the temps were in the 80's throughout most of the trip. Actually when i got home Palm Springs was 99 and i still wasn't having any problems with the bars (and i was running the auto a/c all the time on the trip, but then it's use varies according to the inside temp of the car) A/C seems to be the reason alright. Thanks to all of you for your input on this.
 

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That makes sense. The A/C has to work much harder when it is starting out and everything is hot. Once the temps stabilize, it can handle the higher temps without a big hit on the charge, unless you get stopped for a longer period of time. Glad to hear that your car is doing ok.
 

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One has to think of an AC compressor as a person with a bucket in a boat who's job is to bail out the boat. If he starts his job with the boat fairly swamped and a steady stream of water coming in, he'll be working overtime to get the water level down. On the other hand, if the boat is dry but then springs a leak where he his more than able to keep up, then the boat will stay fairly dry.
 
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