V91 Estim 〈RECENT〉

| Error Code | Meaning | Fix | | :--- | :--- | :--- | | | Internal battery voltage <6.5V during test | Replace batteries (NiMH preferred) | | E-024 | External voltage present on continuity loop | Disconnect test leads. The DUT is live (>50V). | | E-088 | Flash memory corruption | Hard reset: Remove batteries for 10 min. Reinsert while holding "TEST." | | CAL Err | Calibration checksum mismatch | Return to service center. Do not use for safety tests. |

Because v91 is often distributed as an or configuration script , safety depends on your setup: v91 estim