Tesla VCFRONT_a191 — 12V Battery Low

Vehicle Controller (VCFRONT) alert — plain English explanation and what to do next

System

Vehicle Controller (VCFRONT)

Severity

Medium Severity

Dealer visit

Schedule soon

Affects models

All Models

What VCFRONT_a191 means

VCFRONT_a191 means Tesla 12V accessory battery is low. Tesla has two batteries — the main HV pack and a smaller 12V for accessories and computers. A failing 12V can cause unexpected shutdowns even with a full main battery.

What to do

⚠️ Do not ignore 12V warnings. A failed 12V battery can leave you stranded even with full main battery charge.

Keep car plugged in — Charging helps maintain the 12V battery while you arrange service.

Check 12V battery age — Tesla 12V batteries last 3-5 years. Older batteries likely need replacement.

Schedule service — Tesla replaces 12V batteries at service centers. Quick and relatively inexpensive.

Watch for multiple alerts — Multiple unrelated alerts simultaneously often means 12V battery is already failing.

Related Tesla error codes

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