As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CARBON MONOXIDE INDICATION ON ON MAP DISPLAY ON FOREFLIGHT FROM SENTRY PLUS ADS-B RECEIVER. IMMEDIATELY CAME ON WHEN HEAT WAS PULLED ON. TURNED OFF HEAT, OPENED ALL VENTS AND VERIFIED THE SENTRY RETURNED TO NORMAL. SCHEDULE AN INSPECTION WHICH DISCOVERED A HOLE IN THE EXHAUST.