--- title: "Tesla BMS_a074: Max Charge Level Reduced - Cost & Fix | EV Fix Guide" description: "BMS_a074 means a fault inside the high-voltage battery has reduced the maximum charge level and range. Like BMS_a079, the car will only charge when it is below 50%. It is OK to drive, but needs service, which is normally covered by the battery warranty. Tesla Service: $0. Independent: $2,500 - $7,000. Why it is not DIY and where to get it fixed." canonical: https://evfixguide.com/guides/bms-a074-max-charge-level-reduced lang: en last_updated: 2026-10-24 --- [Tesla Model 3](https://evfixguide.com/models/model-3) · [Tesla Model Y](https://evfixguide.com/models/model-y) · [Tesla Model S](https://evfixguide.com/models/model-s) · [Tesla Model X](https://evfixguide.com/models/model-x) Battery & Low-Voltage Professional repair only # Tesla BMS_a074: Max Charge Level Reduced - Cost & Fix By the EV Fix Guide editorial team · Updated October 24, 2026 · [How we estimate costs](https://evfixguide.com/about#how-we-estimate-costs) ## Quick answer BMS_a074 means a fault inside the high-voltage battery has reduced the maximum charge level and range. Like BMS_a079, the car will only charge when it is below 50%. It is OK to drive, but needs service, which is normally covered by the battery warranty. At a Tesla Service Center this typically costs **$0 (Under battery warranty) / $12,000 - $20,000 (Pack replacement, out of warranty)**. An independent shop charges about **$2,500 - $7,000 (Module-level repair, where available)** — potential savings of **50% - 80% (out of warranty)**. **Do not attempt this at home.** ![BMS_a074: Maximum Battery Charge Level Reduced](https://evfixguide.com/assets/images/battery-bench.jpg) ## Symptoms - 'Maximum battery charge level reduced - OK to drive - Schedule service' alert - Charging only starts below about 50% state of charge - Range roughly halved - Charge limit slider set higher than 50% has no effect ## Repair cost: Tesla vs independent shop vs DIY | Option | Typical cost (USD) | | --- | --- | | Tesla Service Center | $0 (Under battery warranty) / $12,000 - $20,000 (Pack replacement, out of warranty) | | Independent shop | $2,500 - $7,000 (Module-level repair, where available) | | DIY | Not possible at home (High-voltage hazard) | | Potential savings | 50% - 80% (out of warranty) | Ranges are US estimates compiled from owner reports and shop quotes; prices vary by region, model year and parts availability. Report your price. ## Can an independent shop fix it? Within warranty, go to Tesla. Out of warranty, an independent EV battery specialist may be able to repair the pack at module level for much less than a replacement pack. Few general garages can do this work. [Get matched with an independent shop →](https://evfixguide.com/?shop=bms-a074-max-charge-level-reduced#find-shop-section) ## How professionals repair it **Safety warning:** There is no safe home repair. You can keep using the car within half its normal range while you arrange service. ### Tools a shop uses - Tesla app and screenshots of the alert - Purchase date and odometer reading (for warranty) ### Steps 1. Keep driving; Tesla says the car is OK to drive. Plan trips around about half your normal range. 2. Charge whenever you are below 50%; the car will not start charging above that level. 3. Screenshot the alert and the charging screen showing where charging stops. 4. Check your battery warranty (8 years, mileage limit by model and year) and book service in the Tesla app. 5. Ask Tesla whether the fix is a module repair or a pack replacement, and whether the replacement pack is new or remanufactured. 6. Out of warranty, get a second opinion from an independent EV battery lab. **Pro tip:** BMS_a074 and BMS_a079 look almost identical to owners: both cap charging at 50%. Mention the exact code when you book, because it helps the technician narrow down the fault. ## Frequently asked questions ### How much does it cost to fix a BMS_a074 battery alert on a Tesla? Tesla Service Center: $0 (Under battery warranty) / $12,000 - $20,000 (Pack replacement, out of warranty). Independent shop: $2,500 - $7,000 (Module-level repair, where available). DIY: Not possible at home (High-voltage hazard). Typical savings versus the service center: 50% - 80% (out of warranty). ### Can I fix a BMS_a074 battery alert myself? No, this is not a safe DIY job. There is no safe home repair. You can keep using the car within half its normal range while you arrange service. ### Can an independent shop fix a BMS_a074 battery alert instead of Tesla? Within warranty, go to Tesla. Out of warranty, an independent EV battery specialist may be able to repair the pack at module level for much less than a replacement pack. Few general garages can do this work. ### Which Tesla models are affected by a BMS_a074 battery alert? This issue is reported on the Tesla Model 3, Model Y, Model S and Model X. ## Related guides - [Tesla 12V / 16V Battery Replacement: Cost & DIY Guide — Independent: $100 - $150](https://evfixguide.com/guides/12v-16v-low-voltage-battery) - [Tesla Charge Port Door Stuck or Won’t Open: Fix & Cost — Independent: $120 - $200](https://evfixguide.com/guides/charge-port-door-stuck) - [Tesla BMS_u029 / BMS_f107 Battery Fault: Repair Cost — Independent: $1,800 - $3,500](https://evfixguide.com/guides/bms-u029-battery-isolation) - [Tesla Pyrofuse Failure: Symptoms & Replacement Cost — Independent: $190 - $320](https://evfixguide.com/guides/pyrofuse-high-voltage-fuse) - [Tesla Frunk Won’t Open (Dead 12V): Model 3/Y Fix — Independent: $50 - $150](https://evfixguide.com/guides/frunk-dead-12v-battery) - [Tesla VCFRONT_a180: Electrical System Power Reduced Fix — Independent: $100 - $300](https://evfixguide.com/guides/vcfront-a180-electrical-power-reduced) This guide is for information only. High-voltage components (orange cables) can be lethal — leave them to trained technicians. Not affiliated with Tesla, Inc.