bad cell 2013 s

[islandbayy]

For those wondering why Tesla is not doing module level repairs instead of replacing with new or remanufactured packs, they actually are. Buffalo, NY Facility is (SLOWLY) tooling up and preparing facility for doing just this. Cannot go into more details at this time however.

 

[maximizese]

Resurrecting an old thread that shows pack failure from cold solder joints. Most HV pack replacements are done by Tesla without any failure mechanism feedback so no stats.

In my auto repair experience, have encountered many ECU/TCM/instrument cluster cold solder joint problems for variety of cars starting in the 2000s when lead-free solder transition started. Seen issues on both Europeans, Japanese vehicles. Computer boards encountered the same problem in this time frame as well. I've fixed about 10x Apple 27" LED displays with same lead-free solder problem (edge lit LED connector solder joint weaken by thermal cycling). Of course the lead-free transition is for environmental/health reasons. However, every laptop board level repair tech knows lead-free solder is much worse than leaded solder for a long lasting solder joint. Lead-free is brittle and cracks with thermal cycling (in computers and auto) and vibration (in auto). Repair techs always use leaded solder in the repair process (softer and much better at handling thermal cycles and vibrations)

An 85kw pack has at least 6x16 (96) solder joints to monitor voltage. They probably don't get much thermal cycling but certainly lives in a high vibration environment. I wonder how many pack failures are similar to post #5 #6 with failed solder joints? OPs issue with module 5 with lower voltage (post #4) measured fine after pulling the module and measured directly (post #17) so BMS solder joint is also the likely suspect. Unfortunately have no follow up from OP.

I guess @wk057 and @Recell might have some stats on this failure mode rather than water ingress or just individual cell failure.

My old 2001 VW Golf TDI had a common issue with lead-free solders. The relay 109 that supplied electricity to the ECM had a finicky solder that would lose continuity under thermal cycling. One second you're driving with full power and the next second it gets incredibly quiet, the needles on the instrument cluster drops, and your instinctively push the clutch in as you try to pull over without power steerings and power brakes. Folks at TDIclub.com believed the lead-free solder was a cheap dab of tungsten or tin that was not durable. VW/Audi refused to issue a recall, but just about every TDI owner on the message board had to replace the relay with a revised version on their own. Fortunately it was an inexpensive part and easy to replace.

I'm hoping Tesla has more durable solder joints, but I think you're on to something and some of the mechanics in the community could shed a lot more light on the topic.

 

[howardc64]

My old 2001 VW Golf TDI had a common issue with lead-free solders. The relay 109 that supplied electricity to the ECM had a finicky solder that would lose continuity under thermal cycling. One second you're driving with full power and the next second it gets incredibly quiet, the needles on the instrument cluster drops, and your instinctively push the clutch in as you try to pull over without power steerings and power brakes. Folks at TDIclub.com believed the lead-free solder was a cheap dab of tungsten or tin that was not durable. VW/Audi refused to issue a recall, but just about every TDI owner on the message board had to replace the relay with a revised version on their own. Fortunately it was an inexpensive part and easy to replace.

I'm hoping Tesla has more durable solder joints, but I think you're on to something and some of the mechanics in the community could shed a lot more light on the topic.

Yes, my lead-free encounters are as follows

For cars

- Volvo P2 (01-07 xc70/v70/s60) DIM (Driver Info Module). DIM display goes crazy. QFP (Qaud Flat Pack) chip solder failing. Likely thermal cycling.
- Volvo ABS control module. Likely vibration.
- 01-03 Rav4 ECM. Few big SMT (surface mount) capacitors solder points failing. Transmission shifts poorly. Likely vibration.
- Mazda 3 TCM. Poor transmission shifts. TCM mounted on top of hot transmission. Likely failure is both thermal cycling and vibration of solder joints.

All 2000-2010 era cars. Typical repair = clean off lead-free solder, reflow with leaded solder. All common problem on these cars.

For electronics

- nVidia/AMD laptop GPU BGA (Ball grid array) solder failures are common on Macbooks
- Vizio/Samsung SmartTV's main BGA SOCs (System on Chip). Cheap smart TVs use lower cost older lithographic node SOCs. Run them hotter to provide smart features with inadequate cooling (often heat sink + ambient air)
- Apple 27" LED displays. Edge lit LED bar connector failure. Multiple LEDs share a single solder point on the connector. Next to last page on this writeup 27 iMac LED reflow.pdf

Hot BGAs are challenging. Hundreds of tiny ball solder points in a grid thermal cycling like crazy. All late 2000s all the way through 2015+ products

Anyway, rampant problem. Tons of macbook pros and Vizio smart TVs gets trashed out in 5 years due to this problem.

 

[spaceballs]

Resurrecting an old thread that shows pack failure from cold solder joints. Most HV pack replacements are done by Tesla without any failure mechanism feedback so no stats.

In my auto repair experience, have encountered many ECU/TCM/instrument cluster cold solder joint problems for variety of cars starting in the 2000s when lead-free solder transition started. Seen issues on both Europeans, Japanese vehicles. Computer boards encountered the same problem in this time frame as well. I've fixed about 10x Apple 27" LED displays with same lead-free solder problem (edge lit LED connector solder joint weaken by thermal cycling). Of course the lead-free transition is for environmental/health reasons. However, every laptop board level repair tech knows lead-free solder is much worse than leaded solder for a long lasting solder joint. Lead-free is brittle and cracks with thermal cycling (in computers and auto) and vibration (in auto). Repair techs always use leaded solder in the repair process (softer and much better at handling thermal cycles and vibrations)

An 85kw pack has at least 6x16 (96) solder joints to monitor voltage. They probably don't get much thermal cycling but certainly lives in a high vibration environment. I wonder how many pack failures are similar to post #5 #6 with failed solder joints? OPs issue with module 5 with lower voltage (post #4) measured fine after pulling the module and measured directly (post #17) so BMS solder joint is also the likely suspect. Unfortunately have no follow up from OP.

I guess @wk057 and @Recell might have some stats on this failure mode rather than water ingress or just individual cell failure.

Yeah I've worked on Roadster packs where ~40% of the ultrasonic welded sense wires have fallen off for some unknown reason (moisture?)