My wife was at a drive-through car wash last week and suddenly the hybrid battery dropped way low. Took at most 3 minutes in car wash.

Today she was on line at a McDonalds drive-in window and the same thing happened. Took at most 2 minutes on line.

Both times she had A/C running. First time car was in neutral but second time was not (park or moving forward).

Red triangle warning indicator flashed and battery indicator was low.

I do most of the driving and have never seen the problem.

Ideas and suggestions?

 

well, 1st idea is to have her checked under warranty. battery, not your wife.

why in the world will she keep car in neutral? or P? i am not sure how it works sitting in place, but driving, if you are in neutral, battery will not charge from inertia recovery.

did the ICE start to charge battery?

but it all does not matter. have battery checked out by dealer.

 

Thanks. Car was in neutral because some car washes require it as the car gets pushed along and wheels freely rotate.

Don't know - she is not alert enough to check for those things.

Car is past regular warranty but is in hybrid warranty. I'd like to see a problem myself because she could not describe it well to me.

 

seriously, no need to push it. red lights and all that came up, let dealer figure it out. you REALLY do not want that to happen in the middle of a desert or something.

it's warranted, let them have at it. don't go into particularities of who was driving, what was going on - just tell them, i had sudden battery drop, red lights, twice. fix it. that's it.

 

Try recreating the event. Battery will drop quickly if using AC and car not moving. Not sure of the red indicator lights. Usually their bad. Might she have misunderstood the lights? sit in driveway with AC on and see fir yourself

 

It is normal for the battery state to drop rapidly when sitting stopped with the AC running. I see that almost every day here in Florida. Running the AC takes more energy than you might think.

When I am stopped in traffic, I normally leave it in "D", with my foot on the brake. I sometimes put it in "P" while waiting for a draw bridge. In both of those states, the engine starts when the car decides that the battery needs to be recharged.

The care will NOT run the engine to recharge the battery while the shifter is in "N". I think I read that here, somewhere. But today the best explanation I can find is on a lexus forum: http://us.lexusownersclub.com/forums...howtopic=65264 :

"From the shop manual - "When in neutral, MG1 and MG2 are shut down. This is because MG1 and MG2 must be stopped electrically as a means of shutting down the motive force, since MG2 is mechanically joined to the front wheels. On the 4WD model, MGR is shut down as well."

"So what this basically means is MG1 is shut down in neutral because MG2 is connected to the front wheels and in neutral you don't want any power going to MG2 from MG1 since you don't want the wheels to be powered. However, MG1 also charges the battery as well as powering MG2, so it can't charge the battery when in neutral because it's shut down so it doesn't power MG2."

 

I finally got some useful info from her.

The first time (in car wash)
The triangular warning lit was blinking. She got "Low T Battery ...". Since shifting to park was not an option, she shut off A/C and problem went away. I told her next time to just press A/C button so car continues to blow air by the A/C coil but turns off the A/C.

The second time (after being on line then occurred at window at McD)
The triangular warning lit was blinking. No other indication except low battery. No message. As soon as she put foot to gas, it went away. Each time she stopped car, she says she put it in park.

We normally leave ECO on but the stupid designers make ECO go off at times. Could be ECO was off which would make A/C drain battery faster.

The first time seems normal. She was in neutral running A/C so it wouldn't recharge battery and gave her proper warning. The second time does seem strange. I think I'll wait and try and leave it in park with A/C on max to test it but she often doesn't pay attention to warnings.

 

You should always turn OFF the AC in the car wash. Not sure what happens, but it's not good for the system (supposedly). I can't remember where I read it, you can search for the story...or just turn it off for a few minutes (a lot easier!)

ECO goes off if you push the temp range to a very high or low temperature. I believe it also goes off if you use the defroster (not sure).
You'll probably not go bankrupt nor cause the ice caps to melt if you use the AC with ECO off for a few minutes, so no need to fret it's odd behavior.

 

Well, in the first case, when car is in neutral, there is no traction battery charging, not even when engine is running, none whatsoever and since you don't know the state of battery charge, when the car was put into neutral, maybe very low already and AC could easily discharge it, bellow minimum, so there is nothing strange about that. Second case is more troublesome, with car in P or D, the engine should kick in and charge battery, never letting it go to bellow minimum, for "x-mas lights" to light up. Since it did, maybe the car was in N after all? or maybe there is some problem.

 

My understanding is that "fresh" mode can pull some of the water into the ventilation system, wetting the cabin air filter. I *always* put mine into recirc mode when I go through a car wash. No problems so far.

You might also want to make sure your wife is in ECO mode going through the car wash. If it's too hot to turn the climate control off entirely, I'd suggest recirc, eco mode, with lower speed fan and a slightly higher temperature set. That should still help keep the car from getting miserably hot without totally draining the battery.

That said, my local car wash takes maybe a minute to get through from the time I put it in Neutral until I'm pulling away.