Cessna Fleet Service Customers
In the past few days we have had a number of issues where the G1000 system tach time and other data that resides in the master configuration module being corrupted when a shop replaced a PFD display.
Please follow the note in the Garmin Line Maintenance manual (or System Maintenance Manual for the Cessna 350 and 400 models) in the GDU104X section for programming and ops checking the LRU's that asks you to program a new GDU-104X display in the MFD position. This prevents corruption of data stored in the G1000 master configuration module, located in the PFD connector backshell.
This note reads:
If replacing the PFD with a new, repaired, or exchanged GDU, the new GDU must be placed in the MFD location and the system files loaded. Move the GDU to the PFD location in the aircraft panel (this step is necessary in order that calibration and other configuration data residing in the config module is not deleted).