BYD Fault Codes & Warnings, Explained in BYD Context
Written and edited by Ethan Cole, Editor-in-Chief · ✓ Technically reviewed by Daniel Wei Chen — Senior Chinese Automotive Diagnostics & Repair Specialist, Sydney · 24 October 2026.
EVs change the fault-code game: much of what matters on a BYD surfaces as dash warnings (“Power Limited”, charging messages) rather than P-codes a cheap reader shows, and BYD’s own control codes are publicly undocumented — we publish the standardised codes we can verify and the warning patterns owners report, each labelled where we have not verified it, and we say where the wall is. One rule above all on any BYD: orange cables and everything they touch are dealer-only. No exceptions.
Codes and warnings covered so far
| Code / warning | Standard meaning | BYD context |
|---|---|---|
| P0562 | System voltage low | By our reading, the code form of 12V bricking: unverified owner reports on the Sealion 6 and Shark 6 (australiancar.reviews, as our research notes recorded it on 22 August 2026; we hold no copy of that source). This list has also named the Atto 3, though we hold no research record of the pattern on that car, and called it the family’s best-documented pattern, and we have not measured that comparison; we no longer call it a family pattern. |
| P0A80 | “Replace hybrid battery pack” | The scariest-sounding code in the book, by our reading. This list has also said that on a BYD the single source we hold points at sensors and software rather than cells. That source is an unverified owner report on the Sealion 7’s Power Limited warning, whose cause our notes give as software or sensor logic, and rarely a physical Blade fault; our notes do not tie that warning to this code. |
| U0100 | Lost communication with ECM/PCM | This list has said: network silence, 12V first, panic last. No research record of ours gives that order for this code, and probing connectors on an EV is a workshop job, as our U0100 page says. |
| “Power Limited” (dash) | — | An unverified owner report on the Sealion 7 (australiancar.reviews, as our research notes recorded it on 22 August 2026; we hold no copy of that source); our notes give software or sensor logic as its cause. This list has also named the Shark 6 (towing SOC management), and called the Sealion 7 and Shark 6 warnings two different mechanisms behind one yellow banner; our notes record the Shark 6 warning from reports we have not verified. |
How to read a BYD fault without fooling yourself
- The 12V battery is suspect #1 for almost any electrical weirdness — it boots the computers that run everything else. That ranking is ours; we have not measured that comparison.
- Screenshot the dash (warning text, icons, when it happened) — BYD service centres work from the exact wording.
- Power Limited on the Sealion 7: our notes of 22 August 2026 on an unverified owner report (australiancar.reviews) say that a power cycle clears the warning for the moment and that the permanent fix is a firmware update, so a warning that keeps returning after power cycles belongs with a service centre. This list has also called a power cycle legitimate first aid in general; our notes record it for this warning only.
- Blade battery panic is usually misplaced: by our reading, LFP chemistry plus the warranty window (see our schedule pages) means cell failure is the rare ending, not the default one. That reading is ours, and we have not measured it.
Correction note: This page no longer calls what it covers documented, and the P0562 row no longer calls the 12V battery pattern a family pattern: it now says that owners report it on the Sealion 6 and Shark 6, that we have not verified it, and that we hold no research record of it on the Atto 3. Two rankings on this page, in the P0562 row and in the list above, are now marked as ours and unmeasured. The order in the U0100 row, the claims about battery cells in the P0A80 row and in the list above, and a general first-aid claim for a power cycle are now marked as what this page has said, with one exception named below: no research record of ours makes them. The Power Limited row and list item are now labelled as an unverified owner report. We withdrew the step that put connectors second in the U0100 row’s order: probing connectors on an EV is a workshop job.
Code definitions per SAE J2012; BYD context from our per-model problems research; the Sealion 7 Power Limited items rest on a single source, australiancar.reviews, as our research notes recorded it on 22 August 2026; we have not verified them, and we hold no copy of that source. BYD-proprietary codes are not publicly documented and are not guessed at here.
Disclaimer: Information on this page is general guidance only and does not replace the manufacturer’s official documentation or the judgement of a qualified technician. Never open, touch or work on any orange high-voltage component. Fault-code behaviour varies between markets, model years and software versions. Last verified: 22 August 2026.