CAS of BATTERY O'TEMP L or R indicates which action?

• A. Takeoff is prohibited, regardless if message clears.
• B. Takeoff may proceed if temp returns to normal.
• C. Continue taxi to runway after message clears.
• D. No impact on takeoff clearance.

Answer: (A)

A BATTERY O'TEMP warning means the battery has overheated, which is a safety-critical fault. When a battery runs hot, there's a real risk of damage, reduced performance, or even thermal runaway and fire, especially under the high electrical load of takeoff. Because of that risk, the aircraft is not authorized to takeoff even if the temperature later returns to normal or the warning clears. The issue must be addressed by maintenance and the system reset only after the battery is confirmed normal. In short, you do not proceed with takeoff until the battery problem is resolved; the warning places a no-takeoff constraint that remains even if the message clears.