2015 P85D - Randomly Shutting Down

[Starbuck]

Hi,
I'm just wondering if anyone has also come across this intermittent issue and if so what Tesla have done about it.

Basically the car has completely shut down on me twice now. To the point where I can't open the doors from the outside.

The first time I had just started super charging at a service centre. (Lucky!) The second time I was 100miles away from home with my extended family and 8 week old baby in the car....not so lucky. This time I had recently supercharged and had a full battery.

What I understand from Tesla is, there is a fault in the High Voltage system that causes it to shut down, but they cannot recreate it and cannot find anything wrong with the HV system that would cause a fault. But it has shut down twice now and has to be towed to a service centre to be reset. This cannot be done by road side assistance.

Two service centres have both spent weeks trying to diagnose the problem, but they don't seem to be able to. Do they have a responsibility to resolve this or replace the car? Only the battery and drive unit are still under warranty, but they can't confirm if there is something wrong with these parts or something else. If they change parts, there is no way to test that it works until/unless it happens again.

 

[dwbv]

How old is your 12v battery? What I've learned thus far is that if your 12v battery goes, your car might as well be a 5k-pound ornament. You may be having intermittent issues with the 12v battery? It may be worth your while to just swap it out with a new battery and see if the issue resurfaces again.

Perhaps take a voltage measurement while connected to the HV battery and disconnected as well to make sure it's within optimal range.

 

[NewbyMaybe]

Mcu1? Was there hot weather? Sometimes my computer quits when the sun cooks it.

 

[MP3Mike]

Do they have a responsibility to resolve this or replace the car?

Doubtful. They only thing they would have a responsibility around is the battery and drive unit, until they are out of warranty, which is probably any day now given it is a 2015.

I'm surprised that they haven't been able to identify the problem. (But then again I haven't seen reports of that type of problem, so it isn't a common thing that happens.) My guess is that it is more likely to be a ground problem than a HV problem. (Grounding points failing is a commonish thing for that age of vehicle and can cause all kinds of weird and intermittent problems.)

 

[Starbuck]

Mcu1? Was there hot weather? Sometimes my computer quits when the sun cooks it.

It wasn't hot weather on both occasions. Apparently they have made it fault again in the service centre but still cannot find the cause as all diagnostics and investigations seem normal. MCU has been replaced under the recall a few years ago as that caused a problem back then.

 

[Starbuck]

How old is your 12v battery? What I've learned thus far is that if your 12v battery goes, your car might as well be a 5k-pound ornament. You may be having intermittent issues with the 12v battery? It may be worth your while to just swap it out with a new battery and see if the issue resurfaces again.

Perhaps take a voltage measurement while connected to the HV battery and disconnected as well to make sure it's within optimal range.

if there was a problem with the 12volt battery would this not be a regular problem? it's happened about 6 months apart. then after a couple of weeks in the service centre. I will suggest this too them as it seems they have focused on the High Voltage system which all seems normal. Two different service centres have had my card for a total of 7 weeks now in the last six months and they are all stumped. The car isn't useful if it shuts down randomly and needs to be towed to a service centre to reset it each time. Technicians said they have seen this sort of thing before but very rarely. Maybe as the cars get older this will become more common.

 

[Starbuck]

if there was a problem with the 12volt battery would this not be a regular problem? it's happened about 6 months apart. then after a couple of weeks in the service centre. I will suggest this too them as it seems they have focused on the High Voltage system which all seems normal. Two different service centres have had my card for a total of 7 weeks now in the last six months and they are all stumped. The car isn't useful if it shuts down randomly and needs to be towed to a service centre to reset it each time. Technicians said they have seen this sort of thing before but very rarely. Maybe as the cars get older this will become more common.

As far as I know this is the original 12v battery. I've asked the question to the service centre and around grounding points. Thanks for the feedback guys. Hopefully can get this car fixed as I don't want to have to get rid of it...especially with free charging these days!

 

[bhzmark]

this is the original 12v battery.

Amazing if true. Start with replacing that as even if not original, still a likely wear item to be replaced.

 

[NewbyMaybe]

Could be a crusty connection they won't find until it shorts completely. Was it raining last time?

 

[Starbuck]

For anyone interested. A lead Technician for the EU has diagnosed the problem as being low voltage being provided from the Battery Management System. He said he's come across this part failing only a few times. This is about £700 part, however I've been quoted £3,500 for parts and labour to make the change. They assure me this will resolve the problem and will come with a 12 month warranty. They did reduce the fee when challenged and have provided a courtesy car even though I don't have a warranty as they need another 6-7 weeks to get the parts in and make the change. In total the car would have been in a Tesla Service centre for 16 weeks on three occasions over 12 months for this problem to be fixed. (Assuming all goes to plan)

 

[NewbyMaybe]

For that much labor it sounds like they're gonna be dropping and opening the battery pack.