NormalModel SModel X600-4000 USD
Model S/X 85 kWh: stuck air valves and moisture ingress into the battery
Old 85-kWh packs are prone to corrosion/leaks through valves/fuse cover → BMS errors, HV shutdown. What to look for and how to fix it.
Battery · 85
Drivetrain · RWD, AWD
Updated · 2025-09-16
Typical picture
- Moisture/condensate gets into the HV battery housing through the breather valves or the fuse block cover → corrosion of busbars/connectors, BMS_F107 errors, etc.
What to check
- Condition of the valves, corrosion of the fuse cover.
- Sealing test of the housing per the manual (low pressure ~0.19 psi).
Repair
- Local leak repair, cleaning/drying, replacement of affected BMBs/modules.
- With deep corrosion — pack removal and bench repair.
Cost in Belarus
≈ $600–4 000 depending on the extent of damage (often $1–2 k).
Links
- Problem overview (valves/AC drain): https://www.autoevolution.com/news/check-the-tesla-model-s-moisture-ingress-problem-with-comprehensive-video-199337.html
- Video: cover corrosion/water in the fuse compartment — https://www.youtube.com/watch?v=GZN8pawcQkg
Sources
- https://www.autoevolution.com/news/check-the-tesla-model-s-moisture-ingress-problem-with-comprehensive-video-199337.html
- https://www.youtube.com/watch?v=GZN8pawcQkg
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