12V Battery drains in 3 days

[nlkruigerm]

My 12V battery drains in 3 days.
Dealer has replaced the WIFI unit, no change.
Second attempt they changed the complete instrument panel (With the speedometer and power display)
Still I can measure that the battery is loosing voltage. Within a day I'm down to 11,9 volts. ( if I stop after a long drive I have almost 14 V)

Any similar experiences and solutions that I can share with my dealer.???

 

[maby]

Get someone to put a current meter in series with the positive connection and pull fuses till the drain stops?

 

[jaapv]

It used to be a bug on some early cars that was solved with an update. Are you running the latest firmware?

 

[user 258]

Get someone to put a current meter in series with the positive connection and pull fuses till the drain stops?

Excellent idea.
Kind regards,
Mark

 

[nlkruigerm]

I guess placing a current meter in series with the battery and pull fuses is what the dealer has done, it is the classic way to find the source of the problem. Of course I'm not sure, I have not been standing next to the engineer.
Maybe there's somebody out there that would like to measure voltage after a long drive and 24 or 48 hr of standstill. It's easy to measure between the chassis and the fusebox in the front, the connection where you should connect the start cables when the battery is dead. See 9.3 in the manual.
I lose 1-2 volts per day.

 

[maby]

I guess placing a current meter in series with the battery and pull fuses is what the dealer has done, it is the classic way to find the source of the problem. Of course I'm not sure, I have not been standing next to the engineer.
Maybe there's somebody out there that would like to measure voltage after a long drive and 24 or 48 hr of standstill. It's easy to measure between the chassis and the fusebox in the front, the connection where you should connect the start cables when the battery is dead. See 9.3 in the manual.
I lose 1-2 volts per day.

That seems very high! The only significant current drain on the auxiliary battery really should be the security system - car alarm and keyless entry. Is there someone within earshot of the car most of the time? The alarm is not tripping, is it? That does draw down on the battery pretty heavily.

 

[user 258]

I guess placing a current meter in series with the battery and pull fuses is what the dealer has done, it is the classic way to find the source of the problem. Of course I'm not sure, I have not been standing next to the engineer.
Maybe there's somebody out there that would like to measure voltage after a long drive and 24 or 48 hr of standstill. It's easy to measure between the chassis and the fusebox in the front, the connection where you should connect the start cables when the battery is dead. See 9.3 in the manual.
I lose 1-2 volts per day.

That seems very high! The only significant current drain on the auxiliary battery really should be the security system - car alarm and keyless entry. Is there someone within earshot of the car most of the time? The alarm is not tripping, is it? That does draw down on the battery pretty heavily.

Does the car have the phone app feature? If so, that is probably the biggest drain, but the 12v battery should be charged each day by the traction battery if the car isn't used (if not used for at least 10 minutes in the 6 hours before 2pm it will start charging and a bleep should be heard inside the car, if I remember correctly).
Kind regards,
Mark

 

[maby]

...Does the car have the phone app feature? If so, that is probably the biggest drain, but the 12v battery should be charged each day by the traction battery if the car isn't used (if not used for at least 10 minutes in the 6 hours before 2pm it will start charging and a bleep should be heard inside the car, if I remember correctly).
Kind regards,
Mark

You think so? I would have thought that the phone app is pretty low drain - a pretty simple microcontroller, real time clock and a wifi receiver - which is probably just polling every few seconds to see if anyone is trying to connect...

 

[user 258]

...Does the car have the phone app feature? If so, that is probably the biggest drain, but the 12v battery should be charged each day by the traction battery if the car isn't used (if not used for at least 10 minutes in the 6 hours before 2pm it will start charging and a bleep should be heard inside the car, if I remember correctly).
Kind regards,
Mark

You think so? I would have thought that the phone app is pretty low drain - a pretty simple microcontroller, real time clock and a wifi receiver - which is probably just polling every few seconds to see if anyone is trying to connect...

Well, that is the reason Mitsubishi decided to charge the 12v battery each day when the car isn't used. The car without wi-fi doesn't get the daily charge if not used. What other conclusion can there be?
Kind regards,
Mark

 

[maby]

...Well, that is the reason Mitsubishi decided to charge the 12v battery each day when the car isn't used. The car without wi-fi doesn't get the daily charge if not used. What other conclusion can there be?
Kind regards,
Mark

Mmmm, I didn't realise there was that operational difference between the wifi and non-wifi equipped cars. Interesting. Clearly there will always come a time when the current drain of any residual systems is going to become a problem - sooner or later the system you describe is going to have to admit defeat and let the auxiliary battery run flat in order to protect the far more expensive traction battery. What is the capacity of the auxiliary battery?

 

[jaapv]

Something like 0.8 kWh.
I did not find the exact value.

 

[Eggtastico]

thats quite worrying.... what if you go on holiday for a week & park at the airport, etc.

 

[maby]

thats quite worrying.... what if you go on holiday for a week & park at the airport, etc.

I would hope that it can manage more than a week, but most cars can deplete their battery by a fair amount in a month or two running the security systems.

 

[jaapv]

If you leave it with a reasonable amount of charge in the main battery it should be fine for months. As I said, there was a firmware bug causing this, but it was solved months ago.

 

[ian4x4]

The explanation of Wi Fi and automatic aux battery charge is here.

http://www.mitsubishi-motors.com/en/products/outlander_phev/app/remote/

36 hrs is the cut off time. I suppose if this control software doesn't get it right the 12v aux battery is in danger of being drained.

 

[ian4x4]

A bit of further investigation.

PHEV 12v Aux battery is rated at 36Ah.

A typical domestic WiFi router is rated at 6 watts.

That means it draws 1/2 amp, so IF I am right the aux 12v battery is flat in 72 hours, if not automatically charged.

Is there a clue here?

 

[DrSlackBladder]

thats quite worrying.... what if you go on holiday for a week & park at the airport, etc.

I would hope that it can manage more than a week, but most cars can deplete their battery by a fair amount in a month or two running the security systems.

Has anyone left the PHEV for a week or two at an airport or similar to verify whether it can be left and still work when you return?

 

[user 258]

thats quite worrying.... what if you go on holiday for a week & park at the airport, etc.

I would hope that it can manage more than a week, but most cars can deplete their battery by a fair amount in a month or two running the security systems.

Has anyone left the PHEV for a week or two at an airport or similar to verify whether it can be left and still work when you return?

Hi,
On a car without faults you don't need to worry. If it has wi-fi and the car isn't used then it will be charged from the drive battery each day. If the drive battery gets too low then it will switch wi-fi off.
And yes, I've left the car at an airport for 8 days with no issue.
Kind regards,
Mark

 

[DrSlackBladder]

I would hope that it can manage more than a week, but most cars can deplete their battery by a fair amount in a month or two running the security systems.[/quote]

Has anyone left the PHEV for a week or two at an airport or similar to verify whether it can be left and still work when you return?[/quote]
Hi,
On a car without faults you don't need to worry. If it has wi-fi and the car isn't used then it will be charged from the drive battery each day. If the drive battery gets too low then it will switch wi-fi off.
And yes, I've left the car at an airport for 8 days with no issue.
Kind regards,
Mark[/quote]

Thanks Mark. I'll often leave mine at an airport carpark for several days at a time.....that could have been disastrous!

 

[maby]

A bit of further investigation.

PHEV 12v Aux battery is rated at 36Ah.

A typical domestic WiFi router is rated at 6 watts.

That means it draws 1/2 amp, so IF I am right the aux 12v battery is flat in 72 hours, if not automatically charged.

Is there a clue here?

A domestic wifi router is a very different beast - it contains a lot more electronics than is necessary in the case of the Outlander wifi interface. The outlander wifi is just a simple wifi receiver and when it's not active, I would expect that it is programmed to wake up every 10 or 20 seconds to see if any device is trying to connect to it. That is just standard "Wake on LAN" functionality which I'm sure Mitsubishi are clever enough to implement. Coupled with low power microcontrollers and a low power real-time clock, it should be possible to get the average current drain down to a few tens of milliamps or lower. Obviously, when a device connects or a timed event occurs, then the whole system will wake up and current drain will increase.