PTT Button Issues?

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PTT Button Issues?

Post by dmloftus »

Recently on a cross-country flight, my son tried to communicate with ATC from the right seat. After repeated attempts were unsuccessful, I transmitted the message to ATC from the left seat. Thinking we had a bad headset/mic, swapping headsets/jacks and switching COM1/COM2 on the same frequency did not resolve the problem but we did notice the COM TX button was illuminated when we pulled the right seat PTT. Just no voice on transmit from the right seat. We were both using Bose A20 headsets. After landing, we swapped several headsets back and forth. Still no solution.
I checked with the local shop and the owner mentioned he has seen problems with PTT buttons getting corroded on other aircraft. He brought out a can of electrical contact cleaner, inserted the tiny hose into the crevice between the PTT button and the center stick housing and started blasting away. He kept his other hand and a rag wrapped around the center stick to minimize overspray. We turned on the master switch and did a radio check on local CTAF and, to my amazement, we got a 5/5 response! I'm guessing the contacts inside the switch must have become oxidized over time (2008 XLS) since the copilot PTT is rarely used.
I'm hoping the problem doesn't repeat and I'm trying to remember to pull the right side PTT switch several times when I fly just to generate some friction on the contact blades of that seldom-used switch. Has anyone had this problem and have you had to replace the PTT switch? Thanks
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