Figure 6-35 Internal Ahrs Calibration Page - Garmin GTX 3X5 Series Installation Manual

Internal AHRS Calibration (GTX 345 Only)
Calibrate the internal AHRS to level (0° pitch and 0° roll). The Internal AHRS Orientation must be set and the aircraft
must be level before beginning this procedure.
190-01499-02
Rev. 9

Figure 6-35 Internal AHRS Calibration Page

Post Installation Configuration & Checkout
GTX 3X5 Transponder TSO Installation Manual
Page 6-26