ESS Pack Service Plug Repair – 3D Printed

ESS Main Battery Pack Service Plug (3D Printed)

The Tesla Roadster ESS main battery pack uses a rear-mounted service plug, buried deep in the left rear quarter panel.  It’s difficult to reach but absolutely critical when a Roadster is bricked, because removing this plug stops any further current draw from the pack and opens the high-voltage interlock loop (HVIL) for safety.

Why these fail

• Aging plastic — After 15–18+ years, the plug body and handle become dry, brittle, and prone to cracking.
• Stuck in the pack — Many plugs have never been removed; years of heat and compression make them stubborn to extract.
• Broken handle — When a stuck plug is pulled, the handle often snaps off before the plug releases, leaving no safe way to remove it.
• Result of broken plug — Once the plug housing is broken, the HVIL microswitch can no longer allow the pack to become operational.
• No new replacements — OEM service plugs are essentially unavailable, and scrapping a pack over a broken handle is not an option.

Our solution

• Rebuild the original plug — We start with your existing ESS service plug rather than trying to substitute a different style connector.
• Precision-machined — The original Service Plug is cleaned and milled down removing the brittle handle housing and a new one installed.
• 3D-printed replacement handle — We 3D manufacture a new handle section that replaces the fragile, broken OEM plastic while preserving geometry and fit.
• Restored HVIL actuation — The built-in pin that drives the HVIL microswitch is re-established so the interlock loop opens correctly when the plug is removed.
• Pack-ready, not a workaround — The rebuilt plug maintains proper electrical integrity and functionality in the Roadster ESS, allowing the pack to be serviced and the car to run.

Service & coverage

This offering is intended for Roadster owners and ESS rebuild shops who have a damaged or broken service plug but an otherwise recoverable battery pack. You send us your plug assembly; we perform the rebuild and return a pack-ready plug with restored mechanical strength and HVIL function.