190-01115-01
G3X/G3X Touch Installation Manual - Troubleshooting
Rev. AC
Page 35-4
If the Airspeed and/or Altitude is failed and shows a Red-X condition as shown in Figure 35-2:
Figure 35-2 Airspeed and Altitude Failure Indications
1. Inspect ADAHRS pitot/static plumbing integrity.
2. Inspect pitot/static ports and associated equipment.
3. If the problem persists replace the ADAHRS with a known good unit.
If a periodic altimeter test, performed with properly calibrated static system test set, indicates that the
ADAHRS static pressure sensor needs to be re-calibrated, follow the procedures described in
for GDU 37X or
for GDU 4XX units.
35.5 Engine Indication Troubleshooting
To troubleshoot an Engine Indication failure (Figure 35-3), gather answers to the following questions.
This information may be helpful to the installer/pilot, the G3X Dealer, or to Garmin Aviation Product
Support in troubleshooting the failure.
Figure 35-3 Engine/Airframe Failure Indications (Reversionary or Split-Screen PFD)
1. Does cycling power restore operation?
2. Did the operator give it sufficient time to start and initialize?
3. Did the problem begin after a software or configuration load?
4. Did the problem happen on the ground or while airborne?
5. Is only the EGT/CHT (i.e. thermocouple inputs) Red-X’d? If so, the GSU 73 configuration
module, configuration module wiring, thermocouple reference, or applicable thermocouple is
defective. Check the wiring and replace the configuration module or applicable thermocouple.
6. Are there one or more temperatures that drop as the electrical load increases? If a temperature
probe shorts (usually where the bayonet is crimped) a ground loop is created forcing the reference
(low side) to increase which causes the temperature reading to decrease.
