[ivo__]

Hello,

My battery keeps going low: the days indicator gets lower, at a higher rate than the actual days. Eg it shows 21 days, one week later it's 5 days. All this despite the car being plugged into the OEM trickle charger. Even weirder than that, the charger always has the green LED to indicate full charge.

I've tried keeping the car locked, keeping it unlocked, keeping it locked with the key away from the car, etc.

The car is always able to start though.

Last time I drove it the battery started at 10-15% and then it went to 43% gradually, and then suddenly jumped to 100%. During that time I got multiple "battery management active" warnings. Then when I restarted the car, those disappeared.

Just bought the car a few months ago, only drove it 4-5 times, taking it to the nearest dealer soon (that would be Italy) - hopefully they'll be able to shed some light about whether this is a symptom of something, but in the meanwhile - has anyone here experienced the same?

 

[Jompen]

Get a new charger. Had same issue as you.

 

[ivo__]

thanks @Jompen - I just assumed it's fine cause the LEDs light up as they should, but I'll get a new one and see what happens

Do you recommend the OEM one or just a CTEK li-ion charger?

 

[invisiblewave]

thanks @Jompen - I just assumed it's fine cause the LEDs light up as they should, but I'll get a new one and see what happens

Do you recommend the OEM one or just a CTEK li-ion charger?

I would try the cheaper one, since what you're doing is trying to eliminate the charger being the problem. Either will work.

 

[GlennReb]

Agreed the charger...I had the same issue. The ctek's work great.

 

[Richard_Wallace]

I think the McLaren is just a rebranded CTEK. Mine also went bad after about 1 year looked like it was working, was not...

I would recommend getting this one

Amazon.com: CTEK (56-926) LITHIUM US 12 Volt Fully Automatic LiFePO4 Battery Charger,Blue : Automotive

Buy CTEK (56-926) LITHIUM US 12 Volt Fully Automatic LiFePO4 Battery Charger,Blue: Battery Accessories - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[The Brigand]

Only 4-5 drives in a couple of months?

You need to drive it more - do a good couple of hours drive if it's stood a while if you can find the time. That's what they are for

 

[Anthony D]

Hello,

My battery keeps going low: the days indicator gets lower, at a higher rate than the actual days. Eg it shows 21 days, one week later it's 5 days. All this despite the car being plugged into the OEM trickle charger. Even weirder than that, the charger always has the green LED to indicate full charge.

I've tried keeping the car locked, keeping it unlocked, keeping it locked with the key away from the car, etc.

The car is always able to start though.

Last time I drove it the battery started at 10-15% and then it went to 43% gradually, and then suddenly jumped to 100%. During that time I got multiple "battery management active" warnings. Then when I restarted the car, those disappeared.

Just bought the car a few months ago, only drove it 4-5 times, taking it to the nearest dealer soon (that would be Italy) - hopefully they'll be able to shed some light about whether this is a symptom of something, but in the meanwhile - has anyone here experienced the same?

Anytime you need someone to drive it for you so it gets more exercise I am available… Just sayin’

 

[ivo__]

Rest assured, the car is driven 😅

It hasn't been in my possetion for a while cause I sent it to Germany to get the suspension accumulators replaced, and I had the battery issue right before sending it. It's on it's way back now and I got a CTEK charger so let's see

 

[Firstkill]

Rest assured, the car is driven 😅

It hasn't been in my possetion for a while cause I sent it to Germany to get the suspension accumulators replaced, and I had the battery issue right before sending it. It's on it's way back now and I got a CTEK charger so let's see

You are using the 12v socket in the frunk?
Sometimes if someone removed the frunk tubs the wires can get disconnected.

or maybe the 12v plug is not installed correctly?

 

[ivo__]

ah that's a brilliant point

I am using this socket but once I pulled it and the whole panel just detached itself and remained in my hand. I did check for loose connections though.. it looked OK but once I have the car I'll check again.

Any alternatives?

 

[ivo__]

actually ignore that - the charger LEDs actually change when it's connected to the battery so this theory can be discarded

 

[Firstkill]

actually ignore that - the charger LEDs actually change when it's connected to the battery so this theory can be discarded

When the charger first cycles, it should always show a low battery, then eventually the LED shows full. If it starts out of full, something is off. Maybe power cycle the charger itself and make sure everything is seated correctly. If not try another charger.

 

[ima2nr (McMedics)]

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[cars4enjoying]

I had this on our 720s it was the charger, looked to be perfectly normal behaviour but after a week or so the car would report 33days instead of the usual 45 days after taking it off charge.

Dealer swapped the changer for a new one, problem solved