[buffaloalan]

I did a quick search and had not seen anything similar.

My x7 was in for routine oil change & multipoint inspection service last week with no issues identified.

Yesterday, as I left work to pick my kid up from school, I had a warning that - I don't remember the exact wording - indicated that the power steering was partially disabled and to call service. I also had a check engine light. I called service and left a message.

As my drive progressed, I received a red alert about the power supply and that I should stop driving. I did not have a safe place to do that, so I tried to make it to the school but the car completely died stranding me in the middle of the road less than a block from the school. The car was taken to the dealership via flatbed and could not be moved from traffic because the entire power system had failed and I could not release the parking brake.

I am waiting to find out what is wrong but this does not exactly fill me with confidence about my extremely expensive vehicle.

Anyone had anything similar occur?

[ppnff]

Originally Posted by buffaloalan

I did a quick search and had not seen anything similar.

My x7 was in for routine oil change & multipoint inspection service last week with no issues identified.

Yesterday, as I left work to pick my kid up from school, I had a warning that - I don't remember the exact wording - indicated that the power steering was partially disabled and to call service. I also had a check engine light. I called service and left a message.

As my drive progressed, I received a red alert about the power supply and that I should stop driving. I did not have a safe place to do that, so I tried to make it to the school but the car completely died stranding me in the middle of the road less than a block from the school. The car was taken to the dealership via flatbed and could not be moved from traffic because the entire power system had failed and I could not release the parking brake.

I am waiting to find out what is wrong but this does not exactly fill me with confidence about my extremely expensive vehicle.

Anyone had anything similar occur?

I've never seen anything like what you experienced. Please keep us apprised of what you learn. Glad everyone is okay - certainly unsettling. Stay well.

[buffaloalan]

Originally Posted by ppnff

I've never seen anything like what you experienced. Please keep us apprised of what you learn. Glad everyone is okay - certainly unsettling. Stay well.

Will do, and thanks.

[blutob2]

I saw a few posts on the FB forums regarding this one. Seems to be coming up more and more often.

[thenew3]

Originally Posted by blutob2

I saw a few posts on the FB forums regarding this one. Seems to be coming up more and more often.

I saw a few on FB but those all seems to be the 50i.
This post is for 40i which has a different motor with a 48v mild hybrid system. I wonder if the mild hybrid system died.

[buffaloalan]

Originally Posted by thenew3

I saw a few on FB but those all seems to be the 50i.
This post is for 40i which has a different motor with a 48v mild hybrid system. I wonder if the mild hybrid system died.

Apparently that’s exactly what happened.

[classj]

Eesh. So how does that repair work? Pull the trans to replace the unit?

[thenew3]

Originally Posted by classj

Eesh. So how does that repair work? Pull the trans to replace the unit?

Why pull the transmission? the 48V motor is belt driven. It's not sandwiched in between engine and transmission like MB does it.

[buffaloalan]

Originally Posted by thenew3

Why pull the transmission? the 48V motor is belt driven. It's not sandwiched in between engine and transmission like MB does it.

I don't know how the repair will work but at this point I'm stuck waiting for a new battery, which will hopefully not take too long.

But my concern is that I have not had an electrical failure in a car since the 1980s. If this mild hybrid battery, which is critically important enough to keep the car going, can just arbitrarily fail after less than a year of ownership and leave me waiting for a tow, what assurance is there that this replacement won't do the same thing within the next 12 months, etc., ad infinitum?

[thenew3]

Originally Posted by buffaloalan

I don't know how the repair will work but at this point I'm stuck waiting for a new battery, which will hopefully not take too long.

But my concern is that I have not had an electrical failure in a car since the 1980s. If this mild hybrid battery, which is critically important enough to keep the car going, can just arbitrarily fail after less than a year of ownership and leave me waiting for a tow, what assurance is there that this replacement won't do the same thing within the next 12 months, etc., ad infinitum?

I was asking classj why he thinks it's necessary to pull the transmission to replace a 48V mild hybrid electric motor.

As far as the 48V battery, That seems to be a very common issue with in the MB GLE/GLS line with 48V mild hybrid system. Seems there's some batch of bad 48V batteries. I wouldn't be surprised if BMW also got a bad batch of 48V batteries.

Since the starter is run off the 48V system. When you came to a stop and the engine start/stop shut it off, that's probably why it couldn't start back up if the 48V battery was bad.

[Wild Blue]

Yikes, haven't seen this one

[classj]

Originally Posted by thenew3

Why pull the transmission? the 48V motor is belt driven. It's not sandwiched in between engine and transmission like MB does it.

Interesting. I was told that it essentially replaced the torque converter.

I guess the dealer was mistaken.