Clunk sound from rear when starting car

[FinallyGotMyM3]

about 80% of the time when I start my RWD LR M3 I hear a “clunk” sound (quite loud) from somewhere behind me. Anyone else have this ? Is this normal or should I take it in at some point ?

 

[hanergy]

I hear it too. Pretty sure that is normal, same with clunks during supercharging.

 

[mike123abc]

Perhaps the main Lithium Ion battery relays connecting? The car has a 12v battery system that runs all the time, and when the car starts up you can hear it connect the Li battery. For me it is just after I open the door I hear the relays connect.

 

[Legolas]

Perhaps the main Lithium Ion battery relays connecting? The car has a 12v battery system that runs all the time, and when the car starts up you can hear it connect the Li battery. For me it is just after I open the door I hear the relays connect.

Yup, for me too. Initially I was concerned but now got used to it

 

[Solidred]

Perhaps the main Lithium Ion battery relays connecting? The car has a 12v battery system that runs all the time, and when the car starts up you can hear it connect the Li battery. For me it is just after I open the door I hear the relays connect.

This is what I was told it was, high voltage system connecting and disconnecting.

Supercharger sound is a different clunk sound.

 

[FinallyGotMyM3]

Works for me ! weird that it doesn’t happen every time though.

 

[Falkirk]

This isn't related to the car starting but have you heard the noise when someone (kids) steps on the floor in the back? Wow it's nuts how it can make that loud noise. I've tested it in a friends 3 as well and it's the same. I thought for sure it was something wrong as well.

 

[FinallyGotMyM3]

Nope. I don’t have any of the “hollow” rear floor board that some of the earlier M3/ have. I’m 49xxx VIN and that problem seems to be corrected. I’ve heard there is a fix for this if you bring it in.

I get the clunk without anyone else in the car.

 

[silentcorp]

There is also the parking break "clunk" too, that one happens all the time as well when first getting in the car.

 

[Falkirk]

Nope. I don’t have any of the “hollow” rear floor board that some of the earlier M3/ have. I’m 49xxx VIN and that problem seems to be corrected. I’ve heard there is a fix for this if you bring it in.

I'll have to check with Tesla about that noise now! I have two friends with a 3 but we all ended up getting it the same day so that's why I thought it was normal. Thanks

 

[eprosenx]

I don’t have any real clunks to report on a daily basis. I can hear the parking break engage and disengage when going into drive, but it is not a clunk. I also hear the HV contractor but it is not that loud.

I have only supercharged twice, so have not noticed the clunks then that others have.

What I *have* heard was a really loud clunk while doing a software update this last time. Normally I am not on the car during those, but my daughter was playing in the car with me and I figure it would be a good way to kill time.

I assume it was the HV relay, but odd that it was so loud only during the SW update. Perhaps it was actuated in a not-normal way during the update?