The upper CDI did not appear to function. I ran a simple test, swapping it for the lower unit. The problem followed the upper CDI.
I contacted the manufacturer for warrenty repair. He insisted on an extensive series of tests, and would not send the requirements for the next test until the previous test was completed. This created endless delays, because I would sert up, conduct the test, then tear things down so other work on the aircraft could be done.
Finally, the manufacturer agreed; the unit was sent back, a broken wire inside the unit was found, and the unit returned. It now awaits some hardware, misplaced during all the testing.
