Battery Management Board (BMB) — Rebuild & Component-Level Repair Service
Roadster • ESS Pack • 1 BMB per Sheet (11 per Pack) • Rebuild Service (No New Units Available)
The Tesla Roadster ESS is built from 11 battery sheets, and each sheet uses a dedicated Battery Management Board (BMB) to monitor cell groups, report sheet health to the pack, and support balancing behavior. A single failing BMB can create misleading faults, interrupt charging, or contribute to a bricked pack scenario.
Important: These BMB boards are no longer in production and there are effectively no new replacements for sale. For legacy Roadsters, rebuilding the original board is the only practical path. This listing is for our send-in rebuild & repair service, performed in our engineering lab.
Engineering lab capability
Our electronics engineering lab regularly performs component-level troubleshooting on legacy Tesla modules and other industrial electronics. We diagnose faults to the component, replace failed devices, and when needed we redesign weak sections (materials, thermal, protection, and signal integrity improvements) to restore long-term reliability on products that are no longer supported by the manufacturer.
What this service covers
- BMB Rebuild (Send-In) — You send us your BMB board; we rebuild it and return the same unit (not an exchange sale).
- Component-level repair — Fault isolation, replacement of failed components, and corrective rework.
- Connector / pad remediation — Repair of damaged pads, traces, and connector-related failures where possible.
- Functional verification — Post-repair validation on a Roadster-relevant test setup prior to return.
Common symptoms of a failing BMB
- Sheet-level faults — Persistent alerts tied to one sheet even after charge attempts.
- Charge interruption — Charging stops due to implausible readings or comms dropouts.
- Voltage/temperature anomalies — One sheet reports values that don’t correlate with the rest of the pack.
- Bricked pack complications — Deep-discharge recovery complicated by BMB comms/sense issues.
At-a-glance
| Where it installs |
Mounted to a single battery sheet inside the Roadster ESS pack |
| Pack composition |
11 sheets per ESS • 1 BMB per sheet (11 BMB boards per pack) |
| Service type |
Rebuild service (send-in) • Component-level repair • Return of your unit |
| What we validate |
Sensing channels, comms integrity, board stability under load/thermal conditions as applicable |
| Best practice |
Diagnose in context (cells + harness + BMB). We can advise on sheet-side checks prior to removal. |
| Requirements |
Board shipped to our facility (or performed during ESS service at Gruber) |
How the BMB rebuild service works
- Remove & send — Ship the BMB board to our engineering lab with fault notes and VIN range (1.5 vs 2.X).
- Bench triage — Visual inspection, connector evaluation, and failure localization.
- Component-level repair — Replace failed ICs/devices, correct cold joints, repair traces/pads as needed.
- Stabilization improvements — Where appropriate, we reinforce known weak points (protection/thermal/material upgrades) to reduce repeat failures.
- Verification — Functional validation on a Roadster-relevant setup before return shipment.
Send your failed BMB boards to:
Gruber Motor Company
203 W. Lone Cactus Dr.
Phoenix, AZ 85027
Attn: Engineering Lab
623-433-8500
USA
Notes: This is a rebuild service for your board (not a new part sale). If the board is physically damaged beyond repair, we will document findings and discuss next steps. Include clear photos of both sides of the board and any fault context to speed turnaround.
