[G39x]

I have a CTEK MXS 5.0 charger and I plugged the charger in to the X7 with the hood open and the doors locked and it has reached to stage 3, however the car keeps on making electrical noises like it is trying to start something or reboot. It is a similar sound to when you go on the BMW app and issue a command like flash lights or sound horn

[thenew3]

Originally Posted by G39x

I have a CTEK MXS 5.0 charger and I plugged the charger in to the X7 with the hood open and the doors locked and it has reached to stage 3, however the car keeps on making electrical noises like it is trying to start something or reboot. It is a similar sound to when you go on the BMW app and issue a command like flash lights or sound horn

How long did you let it sit there? The first time I tried it (using BMW OEM charger which from what I understand is just a rebadged CTEK), I had to leave it there for a couple of days before it got beyond the 3rd led.

[G39x]

Originally Posted by thenew3

How long did you let it sit there? The first time I tried it (using BMW OEM charger which from what I understand is just a rebadged CTEK), I had to leave it there for a couple of days before it got beyond the 3rd led.

I just installed it today, but wanted to ask if the noises are fine. It is making them periodically.

[thenew3]

Originally Posted by G39x

I just installed it today, but wanted to ask if the noises are fine. It is making them periodically.

Yes they are normal. I try to keep my hood as close to closed as possible when I have my battery charger connected. That will reduce the frequency of those noises.

[G39x]

Originally Posted by thenew3

Yes they are normal. I try to keep my hood as close to closed as possible when I have my battery charger connected. That will reduce the frequency of those noises.

I didn't know that, thanks!

Also, I do know that BMW says to not leave the hood closed or let the latches enter the holes as that turns on the 48v system and it won't charge if the hood is latched.

[Mail4loys]

Originally Posted by G39x

I didn't know that, thanks!

Also, I do know that BMW says to not leave the hood closed or let the latches enter the holes as that turns on the 48v system and it won't charge if the hood is latched.

I left my car charging overnight with hood closed and then next day it was complete. Mine is 2020 M50i model, so I think it doesn't have 48v system. About the noice I heard it for the first few mins and then didn't

[G39x]

Originally Posted by Mail4loys

I left my car charging overnight with hood closed and then next day it was complete. Mine is 2020 M50i model, so I think it doesn't have 48v system. About the noice I heard it for the first few mins and then didn't

The owners manual says that the hood needs to remain open for the 48v models.

What was the process that you plugged in the charger?
Mine was get in the car, hold the volume button to turn off screens, open hood, plug in +/-, lock car, and turn on charger, leave hood open.

It went from 1-2 rather quickly, then currently it is on 3, the slow charging isn't bothering me, but it still is making that noise (about 8h now) periodically. I wonder if it is charging up to a point and then the car is discharging itself causing the charger to charge back up the battery.

[G39x]

Update:

So the car is still making those noises, however I noticed the interior lights.

Between the sounds, the hazard light and the light on the glass shifter is on (these are the lights that primarily stay on throughout the charging process),

Then, when the sound occurs, the air suspension light, start stop button light, and the auto beam lights on the left side of the steering wheel turn on. Then after it is done doing whatever it wants, it will turn those off leaving the 2 lights I mentioned previously.

If anyone has charged the x7 or any BMW with the 48v system, can anyone verify the steps and tell me if the repeated sounds are normal?

[G39x]

New Update:

Battery is now fully charged and all lights have turned off inside.

[G39x]

New Update:

So I left the charger on after it went to 7 and this morning it was 7, however, going back just now, it is now back to level 3 with the noises, I am assuming it is due to parasitic loss, however, shouldn't the car go into hibernation after not touching it for this long?

[G39x]

Probably Last Update:

Left it for charging and it went back to level 7 and I unplugged the car after that.

I wonder if the car is trying to charge the other batteries, but as I currently understand it, the 48v battery is disabled with the hood open, however I think because of the many modules, I think there is going to be a greater parasitic loss than some lower BMW models comparatively.

[Mail4loys]

Originally Posted by G39x

...

What was the process that you plugged in the charger?
Mine was get in the car, hold the volume button to turn off screens, open hood, plug in +/-, lock car, and turn on charger, leave hood open.

...

I didn't follow any specific process or order. This is what I did

Unlocked car, open hood, connected +/- and turned on charging, closed the hood, lock the car and walked off after checking the charger for status/error (was at 3rd step).

After leaving it overnight came next day morning and saw it was fully charged, unplugged the charger and started driving

[Qsilver7]

Just curious why the vehicle needs to be locked? Is it not in a secured location (like your home’s garage)?

[G39x]

Originally Posted by Qsilver7

Just curious why the vehicle needs to be locked? Is it not in a secured location (like your home's garage)?

No real safety reason, I believe the car stays off when it is locked and has less parasitic loss due to it not trying to actively search for the key. For example, if you have comfort access on and you don't drive the car for a few days with it locked, the car doesn't unlock when you get close. (It does open as soon as you touch the handle though).

[Qsilver7]

Thanks for the explanation. When the car is locked using the remote or CA (comfort access) etc…the DWA (anti-theft alarm system) is activated. The interior motion sensor, tilt sensor, and all the other monitors (alarm siren/doors/hood/trunk/status LED below rear view mirror) are all on alert & active. If the vehicle was unlocked…that system would not be active.

I wonder if your charging cycle would react differently if it was hooked up to the engine bay locations and the car was left UNLOCKED. As long as a remote fob didn’t come into close proximity…there would be no communication calls over the car’s bus system.

Just a thought.

[G39x]

Originally Posted by Qsilver7

Thanks for the explanation. When the car is locked using the remote or CA (comfort access) etc…the DWA (anti-theft alarm system) is activated. The interior motion sensor, tilt sensor, and all the other monitors (alarm siren/doors/hood/trunk/status LED below rear view mirror) are all on alert & active. If the vehicle was unlocked…that system would not be active.

I wonder if your charging cycle would react differently if it was hooked up to the engine bay locations and the car was left UNLOCKED. As long as a remote fob didn’t come into close proximity…there would be no communication calls over the car’s bus system.

Just a thought.

I tried it with it being unlocked and it was doing the same thing (the noises), so I don't think it made any difference, but I didn't want to mess up the charging by unlocking the car and waking up everything, so I left it locked, so I don't think it makes a difference, unless parking outside, then there is a security risk lol.

[swarick]

I'm a new X7 owner and am curious why your battery needs charging? Is your alternator not working?

[G39x]

Originally Posted by swarick

I'm a new X7 owner and am curious why your battery needs charging? Is your alternator not working?

Haha, no, not driving it much and the car is in storage for now.

The newer BMW's have a lot of electronics that run after you turn off the car and this causes parasitic loss, and this may cause the battery to go down if you don't drive it on a regular basis, but a battery charger helps the battery stay in better health.

It's not needed, but recommended if the car is not driving much.

[swarick]

Thanks for the reply. I'm enjoying mine too much to let it sit for very long

[Mail4loys]

Originally Posted by G39x

Haha, no, not driving it much and the car is in storage for now.

The newer BMW's have a lot of electronics that run after you turn off the car and this causes parasitic loss, and this may cause the battery to go down if you don't drive it on a regular basis, but a battery charger helps the battery stay in better health.

It's not needed, but recommended if the car is not driving much.

+1 … I was out of station for a month and didn't use X7 during that time. So kept it one charge while I was out

[G39x]

Originally Posted by swarick

Thanks for the reply. I'm enjoying mine too much to let it sit for very long

One more thing, if you are going to leave it for a bit, make sure to invest in one, I have heard some people whose batteries died on their BMW and it caused a lot of error that needed to be taken into service to reset and it took them a while to get the car back.

[stockguru]

Originally Posted by G39x

One more thing, if you are going to leave it for a bit, make sure to invest in one, I have heard some people whose batteries died on their BMW and it caused a lot of error that needed to be taken into service to reset and it took them a while to get the car back.

Not sure what definition of long time is but I've gone a month a couple of times the past year on a 2020 x7. I have found that it shuts off and hibernates after some time (not sure how long) so it no longer wakes and unlocks on comfort c access when you approach. This likely saves the batteries. Started up with no issues and battery appears to be around 40% when connecting to charger. Interestingly enough, I find the battery drains really fast when you charge to 100% and never sits there. After one drive it's back down. Basically it likes to sit between 40-60%, I'm guessing programming? I was charging the car all the time after first buying it and thinking there was a battery problem but have now just let it be.

Note, I did not connect dash cam or radar detector. If you have, then I would definitely have it on tender as those will battery drain