The mysterious missing 10kWh.

[Kohler Controller]

I had the strangest thing happen to me yesterday. Somehow I lost ~10kWh. Is Encyclopedia Brown on the list? I could use your help.

Here are the facts:
My average daily usage 60 miles. Driving pattern does not deviate much.
Recharge time typically takes ~3 hours using 240V/30A EVSE.
Fully charged (extended setting) started at 11:30 pm Tue night.
Full charge (ext) ended at 2:30 am Wed morning.
115 miles of estimated range when starting Wed morning commute. 60F ambient.
Dropped off kid at school and drove to work, 31 miles, no A/C or heat on. (I did not notice est range after I parked),
Drove to lunch, ~5 miles. 75F ambient, A/C on. (again, did not notice est range)
On way back to office, noticed range down to 13 miles! Bars down to 3. YIKES! Where did my range go? I should be showing >60 miles on the GOM.
At first I was thinking the GOM value just freaked out, but because the bars were also low, I was a little worried.
Charged at 2.8kW for 3 hours. GOM showed 33 miles.
Drove 22 miles back home. GOM showed 13 miles and only 1 bar. Extremely Low Voltage alarm. Usually this doesn't come on until <7 miles.
Total daily distance driven 73 miles.
So at this point I'm wondering if I'm going to put 3 hours of charge back in, which would mean the GOM is just bonkers. But if I charged for more, it would mean I really did consume more energy somehow.
Recharged (ext) Wed evening. Started at 8:43 pm, ended at 2:15 am (5.5 hours at 7.4kW). ~40kWh returned!
However, EV efficiency reported by EnTunes for Feb 11 (3.5 miles/kwh).
GOM showing 125 miles Thus morning.

So how did my car burn up ~10kwh between 8am and lunch?

 

[fromport]

I had the strangest thing happen to me yesterday. Somehow I lost ~10kWh. Is Encyclopedia Brown on the list? I could use your help.
[SNIP]
So how did my car burn up ~10kwh between 8am and lunch?

Tony showed me that the RAV4 takes up a solid 2 amps from the batteries when in the ON position.
time 3XX volt that is somewhere between 0.65-0.75 kWh per hour.
I once accidentally left my car on for about 1 hour.
4 hours would burn 3 kWh, certainly not 10.
Tony also pointed out that the battery heater is 6Kw. If it was really cold when you started, that could have burned up some extra electrons as well, but you are probably familiar with less range under cold(er) conditions.
Sure sounds strange

 

[Kohler Controller]

I had the strangest thing happen to me yesterday. Somehow I lost ~10kWh. Is Encyclopedia Brown on the list? I could use your help.
[SNIP]
So how did my car burn up ~10kwh between 8am and lunch?

Tony showed me that the RAV4 takes up a solid 2 amps from the batteries when in the ON position.
time 3XX volt that is somewhere between 0.65-0.75 kWh per hour.
I once accidentally left my car on for about 1 hour.
4 hours would burn 3 kWh, certainly not 10.
Tony also pointed out that the battery heater is 6Kw. If it was really cold when you started, that could have burned up some extra electrons as well, but you are probably familiar with less range under cold(er) conditions.
Sure sounds strange

I thought about leaving the car on too, but it won't let you lock the doors with it on, and I always lock when I get out. I even remember unlocking the door and hearing the beep before I got in it to go to lunch.

As for the heater, that can't be it, as my heater is broken. But thanks for trying!

 

[TonyWilliams]

As for the heater, that can't be it, as my heater is broken. But thanks for trying!

There are two 6kW heaters on board; one for the cabin and one for the battery.

 

[Kohler Controller]

As for the heater, that can't be it, as my heater is broken. But thanks for trying!

There are two 6kW heaters on board; one for the cabin and one for the battery.

So one theory might be there was a glitch in the battery coolant temp sensor (thinking the batteries were super cold, even though it was 65-70F ambient), then turned on the pack coolant heater (at 2.5kW level), and that I had to leave the car ON (as our systems do not have active cooling when the vehicle is off). Possible, but I think I'm reaching here.

On a different note, during cabin pre-conditioning, the most it pulls from the wall that I've seen is 3A at 240V (~750W), even on cold mornings. Wouldn't the battery coolant heater pull more power from the wall if it was pulling up to 6kW to warm up the batteries?

 

[TonyWilliams]

On a different note, during cabin pre-conditioning, the most it pulls from the wall that I've seen is 3A at 240V (~750W), even on cold mornings. Wouldn't the battery coolant heater pull more power from the wall if it was pulling up to 6kW to warm up the batteries?

I don't know about preconditioning, since it would stop as soon as I opened the door, but the onboard heater is definitely pulling 17-ish amps at battery voltage.

What you're measuring is AC power into the onboard battery charger. Since the heater pulls from the battery, not an AC source, there's not necessarily any direct connection between the two.

 

[Kohler Controller]

On a different note, during cabin pre-conditioning, the most it pulls from the wall that I've seen is 3A at 240V (~750W), even on cold mornings. Wouldn't the battery coolant heater pull more power from the wall if it was pulling up to 6kW to warm up the batteries?

I don't know about preconditioning, since it would stop as soon as I opened the door, but the onboard heater is definitely pulling 17-ish amps at battery voltage.

What you're measuring is AC power into the onboard battery charger. Since the heater pulls from the battery, not an AC source, there's not necessarily any direct connection between the two.

Why in the world would they not use AC power to pre-condition everything when connected?

 

[TonyWilliams]

On a different note, during cabin pre-conditioning, the most it pulls from the wall that I've seen is 3A at 240V (~750W), even on cold mornings. Wouldn't the battery coolant heater pull more power from the wall if it was pulling up to 6kW to warm up the batteries?

I don't know about preconditioning, since it would stop as soon as I opened the door, but the onboard heater is definitely pulling 17-ish amps at battery voltage.

What you're measuring is AC power into the onboard battery charger. Since the heater pulls from the battery, not an AC source, there's not necessarily any direct connection between the two.

Why in the world would they not use AC power to pre-condition everything when connected?

Because the actual components are all 300-400VDC powered. Particularly at high SOC, the battery can't accept much power, and those two heaters can consume more than the 8.1kW DC max that can go into the battery.

 

[fooljoe]

Somebody borrowed your car and took a joyride while you had lunch. :lol:

Seriously though it sounds like there could be a real problem with your battery. I'd take it in to get it checked out, and keep a detailed log of bars/miles going forward in case it happens again. If you used RavCharge I could dive into the server logs to look for clues.

 

[Kohler Controller]

Somebody borrowed your car and took a joyride while you had lunch. :lol:

Seriously though it sounds like there could be a real problem with your battery. I'd take it in to get it checked out, and keep a detailed log of bars/miles going forward in case it happens again. If you used RavCharge I could dive into the server logs to look for clues.

I can't "take it in", as I'm an out of stater. Unfortunately, I let my RavCharge subscription lapse back in October. I have since resubscribed.
Yesterday I drove 127 miles on the car without issue.
But this morning, I woke up to find that it failed to charge (I have it set up to charge by 5am everyday). It has been reliably charging on the timer for years. Don't know if anything is related or not. I'm switching programming over to Charge Upon Plug In, and buying RavCharge again.

 

[Blastphemy]

I thought about leaving the car on too, but it won't let you lock the doors with it on, and I always lock when I get out. I even remember unlocking the door and hearing the beep before I got in it to go to lunch.

You can absolutely lock the doors with the car on; you just have to do it manually. Take the mechanical key out of the keyfob and lock the driver's door with it while the car remains on. The alarm will not sound and the keyfob will not unlock the door. Use the mechanical key to unlock the driver door when you return to the car.

See page 94 of the owner's manual.

 

[Kohler Controller]

I thought about leaving the car on too, but it won't let you lock the doors with it on, and I always lock when I get out. I even remember unlocking the door and hearing the beep before I got in it to go to lunch.

You can absolutely lock the doors with the car on; you just have to do it manually. Take the mechanical key out of the keyfob and lock the driver's door with it while the car remains on. The alarm will not sound and the keyfob will not unlock the door. Use the mechanical key to unlock the driver door when you return to the car.

See page 94 of the owner's manual.

You are correct, of course. But in the context of my story, I couldn't have locked the doors by touching the button on the door handle, which is how I always do it. Thanks for the info though, in case I do need to leave it on for some reason.