What was found
DURING CLIMB AROUND 8,000 FT, THE MASTER WARNING LIGHT ILLUMINATED WITH NO INDICATION WHY. IT WAS RESET & IT ILLUMINATED AGAIN WITH A BATTERY OVER TEMP ABOVE 160 FLASHING ANNUNCIATOR LIGHT. THE MASTER WARNING LIGHT REPEATEDLY ILLUMINATED AFTER BEING RESET. THE BATTERY TEMP GAUGE INDICATED A STEADY 73 DEGREES. AFTER A PRECAUTIONARY LANDING, 10 MINUTES LATER, THE BATTERY CASE FELT COOL TO THE TOUCH. FOUND BATTERY INTERNAL TEMP PROBE FAULTY. R & R BATTERY WITH TESTED SERVICEABLE UNIT IAW MM CHAP 24-21-00. OPERATIONS CHECKED GOOD. NO FURTHER FAULTY TEMP INDICATIONS.