FX3: intermittent zero amps, spiking oil temp, strobes tripping off

[Andy]

It still sounds to me as though there are two separate issues.

Whatever the malfunction of the strobes, the alternator should be able to keep the battery current positive after engine start.

There is no external strobe controller. The strobes are synchronized by a shared "sync" wire. The flash pattern is more complex than seen by the eye as each visible flash is made up of 3 shorter flashes. (Stobes as fitted to FX-3 serial 100.)

[hawgdrvr]

These lights these days are quite computerized and as you mentioned Andy there is more than meets the eye in how they strobe and sequence. I posted my saga from the beginning of the year on Flightinfo.com with my landing light upgrade. Long story short after working with Pete and Mark in figuring out why I was com jamming myself with the lights on, static on the radio, ensuring I had a good ground, etc. etc. in the end it was a defective light. WAT was great to work with and I could not praise them enough for their support and handling of that matter. I bought the lights from aircraft spruce, WAT sent me replacements and the problem was instantly solved. WAT's replacements were manufactured a year later than what aircraft spruce shipped with 2021 lights (in Jan of 2024). It was presumed to be a bad voltage regulator within the light. Moral is, these lights are computers. A bad board, component, etc. can cause issues as described, is my guess. Chase it for days, weeks, months or replace and see if that resolves it. AeroLED's or WAT (one in the same now I think) would probably warranty replace or offer advice to test. Just hope you can find resolution and go enjoy that amazing plane @cavok.

[hawgdrvr]

Hmmm, the sync wire sounds suspect, I wonder if there is a bad connection somewhere with that?

Couldn't you easily pull the 3 light assemblies out and bench test them? All you should need is a 12V source (i.e. starter battery). You could even pull the on/off toggle switch from the panel and mock up the same wiring with power and sync wire I presume and see if you can reproduce the issue in a bench test?

[Andy]

Hmmm, the sync wire sounds suspect, I wonder if there is a bad connection somewhere with that?

The wiring schematic shows 2 plug breaks in each of the 3 strobe/nav light wire runs (for the wings I expect those connectors are at the root and tip). There is also a bundle of wires and blade connectors in the Nav/Strobe light jumper wire assembly between the panel and fire wall.

There is lots of potential for a bad connection. Intermittent faults can be very hard to find but, if I understand the strobes and nav lights, it should be possible to disconnect any two and still have the remaining one work correctly.

I believe this reference is correct for my nav/strobes but I don't know what range of FX-3 serial numbers it would be applicable to. (Pete- do you have a better reference for the strobes fitted to this problem aircraft?)

https://www.aveoengineering.com/down...traDayLite.pdf

I also have a mod 3 version on file but have not checked what the differences are. The mod 4 data sheet is later than my build date.