Had to choose between two ways to test a faulty transponder on a Cessna 172

The transponder kept failing the 4096 code test. I could either pull the whole unit and bench test it, or try to trace the coax line back from the antenna first. I went with tracing the line, and found a bad BNC connector near the tail that was letting in moisture. Fixed the connector in about an hour and the test passed. Anyone else find themselves skipping the bench test to check the simple stuff first?

3 comments

3 Comments

milessmith9d agoMost Upvoted

Ever notice how the simple fix is usually hiding in plain sight?

umar5910d ago

Man, reminds me of the time I chased a radio issue for days before finding a chewed wire in the avionics bay.

wesley38510d ago

Tracing the line first saved you a whole lot of bench time.