SEALION 7 completely unresponsive: safe 12V checks

Record the pattern

1. Try the normal smart key and spare key once, away from other electronics.
2. Note whether any interior light, exterior light, lock sound, screen, charging-port light or warning responds.
3. Check whether the vehicle is connected to a charger and record any message shown by the charge point.
4. Think back to a recent OTA installation, long parking period, accessory use or warning, but do not assume it proves the cause.

Do not improvise electrical work

Do not touch orange cables or covers, dismantle trim, connect a booster to an unconfirmed point, reverse polarity or repeatedly wake the vehicle through apps and handles. The exact recovery or external-power procedure must come from the current SEALION 7 handbook or trained roadside support.

When urgent help is needed

Keep away and call emergency services for smoke, heat, unusual odour, damaged high-voltage components, collision damage or water ingress. Otherwise contact BYD roadside assistance or an authorised repairer and report the response pattern, parking duration, charging state and recent software activity.

After recovery

Ask for the cause and test results to be recorded rather than accepting an unexplained reset. Confirm that charging, locking and software-version displays operate normally before relying on the vehicle again.