Battery drain issues on my 2-month-old Innova Hycross: Any fix?

I kept one key near the gear lever, and another next to the steering column thinking the proximity sensor would detect it.

BHPian sameerg recently shared this with other enthusiasts.

My two-month-old Hycross has faced battery drain issues twice now. The first time it happened was when the car was just a week old, service centre folks said it was due to the car being driven at low speed. Which leads to cars running mostly in EV mode and engines not being used enough. I felt it was a stupid argument but since I was travelling and my father was dealing with the service folks, I didn't debate much.

Update: This morning, the car didn't start again. Has anyone else faced this issue? Any idea why this would be happening?

The first time, the car didn't start (I don't know the details since Dad faced the issue). I think it was a 12v battery since Toyota Folk connected another battery to the 12v battery and started the car. My dad drove the car for a few km to charge the battery, and everything was fine.

This time again, I suspect it is a 12v battery. Here is the sequence of events that happened this time...

We used the car on the 1st of June evening and parked it. 3rd June (today) morning when I got into the car, It showed the error-"key not not detected". So I got both the keys, but still the same error. Then I kept one key near the gear lever, and another next to the steering column thinking the proximity sensor would detect it. Till then, the instrument cluster was on, ..... but in a few seconds, the car just died. Everything stopped working.

Again Toyota folks came, used the battery and started the car. They have taken it with them to the service centre. What they are saying is

1. There could be some sort of "leakage" from the 12V battery which leads to drainage from it
2. A hybrid battery kicks in to charge the 12V battery draining it
3. Because of low overall usage that too at low speeds, the hybrid battery doesn't get charged enough...leading to both batteries being dead.

I am not sure if this is true or even possible. This is what the guy who picked up the car said or at least what I think he said. Will be visiting the service centre tomorrow to understand more.

What is funny in the entire episode is that just last week, I was facing issues with my 10-month-old Kodiaq regarding its rain-sensing vipers. As usual service centre folks had no clue as to what was wrong. My father was on to me about disregarding his advice and buying a Kodiaq instead of a Fortuner. Now I have both the vehicles in the service centre with no clue as to what is happening to either of them

Here's what BHPian dearchichi had to say on the matter:

I have a 6-week-old HyCross VX that's not been driven much (1300 km to date). I'm the only driver thus far, and I drive a low speeds (largely below 80 KMPH). Most of the time, the hybrid battery is charged up to 3 bars, very seldom up to 6 bars and never beyond. My mileage ranges from 19 to 27 KMPL, implying the hybrid battery gets used often. I've never faced a dead-battery situation thus far.

Do you have a dashcam running with parking mode enabled? Perhaps that could leech the charge beyond the low-voltage levels.

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