12v battery keeps going flat

[Sestrel]

Does this problem exist in the Mk 4 RAV as well?

[philip42h]

33 minutes ago, Sestrel said:

Does this problem exist in the Mk 4 RAV as well?

This 'problem' exists in all cars - if you leave the car standing too long the Battery will run flat. With ICE cars that is most likely to lead to the situation where the engine won't start.

It is more pronounced with EVs and hybrids due to the smaller size of their auxiliary batteries. They don't have / need starter batteries because there is no starter motor to turn.

The 4.4 hybrid will have the characteristics of any other Toyota hybrid. A 4.4 ICE will have the characteristics of an ICE.

[Sestrel]

This is the first hybrid I’ve had, so I assumed it wasn’t the same as a normal ICE starter Battery. 

[Derek.w]

12 hours ago, philip42h said:

This 'problem' exists in all cars - if you leave the car standing too long the battery will run flat. With ICE cars that is most likely to lead to the situation where the engine won't start.

It is more pronounced with EVs and hybrids due to the smaller size of their auxiliary batteries. They don't have / need starter batteries because there is no starter motor to turn.

The 4.4 hybrid will have the characteristics of any other Toyota hybrid. A 4.4 ICE will have the characteristics of an ICE.

I use to have the same problem so used a mains charger when voltage dropped below 12.3 volts.

Now moved over to solar charging but ended up connecting 3 solar panels to a solar charge controler. Have not used mains charging in over 2 month now.

The days at around 13 volts max are useing just two solar panels.

[David Alderson]

Hey everyone, hoping you can advise. I have ordered a 2024 RAV4 PHEV. 

We go to Australia to visit family for up to 6 weeks every year. Will the Battery still go flat when the car is standing on the drive for this period, or have Toyota fixed the issue?

thanks for your help. 

[philip42h]

51 minutes ago, David Alderson said:

Hey everyone, hoping you can advise. I have ordered a 2024 RAV4 PHEV. 

We go to Australia to visit family for up to 6 weeks every year. Will the battery still go flat when the car is standing on the drive for this period, or have Toyota fixed the issue?

thanks for your help. 

There's no 'issue' to fix - it's a feature of modern cars.

If you are going to be leaving the car standing for six weeks or so, you would be well advised to make arrangements to top-up the auxiliary Battery during that time. How best to do that will depend on where the car is standing. If the car is out in the open a solar charger might work well; if it is garaged use a mains powered smart charger ...

[Rigsby]

3 hours ago, David Alderson said:

Hey everyone, hoping you can advise. I have ordered a 2024 RAV4 PHEV. 

We go to Australia to visit family for up to 6 weeks every year. Will the battery still go flat when the car is standing on the drive for this period, or have Toyota fixed the issue?

thanks for your help. 

If you are able use a smart charger, something like a CTEK or NOCO, they can safely be left connected while you are away.

I now carry a NOCO GB40 jump starter pack for peace of mind.

[Nick72]

DCM module software update fixed this issue for me. I've left the car for over 3 weeks and it starts first time despite hardly any use and only very short journeys prior.

Before the update I couldn't leave the car 2 days without having a flat 12V.

Still, I carry a moco with me just in case. Keep it in the glove box for easy access.

The issue is the tiny 12V Battery which under normal conditions is fine in terms of capacity. But any slight issues with excessive current drain when the car is OFF more readily manifest as a won't start problem. 

[ernieb]

+1, solar charger if the car can be left out side.

[philip.banner@btinternet.c]

A cautionary tale.

Don't park your hybrid with the side lights left on, as when you return, you may not be going anywhere. 

[Paul john]

2 hours ago, philip.banner@btinternet.c said:

A cautionary tale.

Don't park your hybrid with the side lights left on, as when you return, you may not be going anywhere. 

How is that possible when the hybrids have a “you have left your lights on alarm” and really complain. 
you would have to leave your “side lights” on and the doors unlocked. Which would lead to way mor issues than a dead hybrid after 14 days or so…