Cessna Model 172S Skyhawk SPArcing Avionics MasterPilot reported burning smell and failure of avionics #2 buss during run-up. Troubleshooting revealed the right side of the avionics master switch (#2 buss) had been arcing internally. Replaced switch; ops check okay.
Aircraft master and avionics master switches frequently experienced failures across various models, including internal arcing, manufacturing defects, corrosion, and foreign object debris.
These failures resulted in critical operational issues such as burning smells, loss of avionics, spiking circuits that damaged other components (e.g., transponders), and inability to reliably control aircraft power.
In almost all reported cases, replacing the faulty switch resolved the issue, restoring normal system function.
Cessna Model 172S Skyhawk SP Arcing Avionics Master
Pilot reported burning smell and failure of avionics #2 buss during run-up. Troubleshooting revealed the right side of the avionics master switch (#2 buss) had been arcing internally. Replaced switch; ops check okay. Part total time: 1018.0 hours
CREATE A FREE ACCOUNT
Sign up to keep reading
Create a free account to continue. Already a member? Sign in below.
