v2 Pack Sense Wire Repair

The only v2 pack I have ever touched personally is happily in my car right now and hopefully it stays there.  I don't have any hands-on experience with these packs but from what I read online, their 'fatal flaw' isn't the BMB boards - it is the design of the new sensor wire attachment.  This Thread on TMC has some great information from AlphaTango11 and follow up discussion after post #65.  The whole thread is worth a read as it has a bunch of great info. 

One of the international vendors shared in the Facebook groups that they believe these failures have more to do with thermal expansion than it does with impacts and vibration.  The basic theory is the physical module expands at a different rate than the rigid 'flex' cable (not a very accurate name!) and the little welded connections on the copper pads fatigue and break off.  The true answer could be a combination of these factors but the bottom line is that the sense wires on these packs are much more fragile than the earlier version that uses the single stranded wire welded to the collector plate.

Everyone agrees these are difficult to reattach correctly.  Some vendors are trying a conductive epoxy.  Some suggest a solution like the epoxy would be good to apply before the connections fatigue and break.  Others are looking for a vendor with experience building wiring harnesses might build a retrofit kit that can plug into the BMB and remove the (non-flexible) flex cable.  These v2 packs just started coming off warranty in 2024 so before now Tesla has been dealing with them.  It is fair to say this will be at least as frequent a failure mechanism as the BMB capacitors in the v1 packs.

If I have an occasion to open one of these personally or if a consensus grows in the community about the best way to fix this, I will be sure to update this page.