About 6 weeks ago the ‘low voltage’ warning light appeared while in flight and the amps/volt meters were negative. After getting down…the main CONNECTOR on the back of the alternator had detached. This was very LOW grade…thin aluminum which split at the beginning of the ‘loop’ after the crimp.
Two weeks ago…ALL the gauges on the right panel starting jumping the same day my flaps had failed. So, I thought it was an electrical issue related to the flaps…After pulling the ‘flaps’ breaker…still had the ‘jumping’. Upon replacing the relays…the flaps worked fine…the gauge ‘jumping’ was still there…After some lenghty sleuthing on my part…the SECOND thin wire on the back of the alternator was ‘hanging on by a thread’. The connector was ‘crimped’ only once at the inside edge allowing the wire to jiggle and arc. After replacing this connector…all was still!!
Now during preflight…I slightly pull on both alt. wires (they are easy to reach) as well as inspect the belt.
This is obviously less of a problem with dual alt. systems. However, I would certainly have my local FBO upgrade these connectors anyway.
FINNALLY, WHEN REPLACING THE FLAP RELAYS…THE HEAD MECHANIC WAS ‘SHOCKED’ TO SEE THE FLAP ACCTUATER “BONDED” TO THE GUSSETT WITH ADHESIVE AND ‘NOT’ THRU BOLTED. HE SAID IF THIS TEARS LOOSE…IT WOULD BE CHUTE TIME! I GUESS IF A WING COMES OFF…WE GOT THE SAME ISSUE. BUT, A COUPLE OF BOLTS COULD NEGATE THE FLAPS ANYWAY!
Top Gun Aviation just replaced the Molex connectors that carry the fuel flow signals through the metal plate just forward of the firewall (what is that plate called? the second firewall?).
The symptom was that the fuel flow would be about right at low RPM and gradually got too high at high RPM. The vibration from the engine caused spurious pulses on the signal lines, or that’s our theory anyway.
The Top Gun folks didn’t think much of using Molex connectors in aircraft and they replaced them with a kind of connector used in Moneys which I think they called “knife connectors”. That fixed the problem.
I think it is odd that Cirrus used such fine and expensive connectors for some things (like the MCU) and cheap connectors other things. It makes a little sense, in that the more important things have better connectors, but how much does it really cost to just use the good ones everywhere. From looking through the plane, I think the answer is “very little”.
Anyway, if you have a problem with a signal carried on one of these cheap connectors, I suggest you consider my experience.
Cirrus customer support didn’t have a problem with the connector change even though the new one isn’t what is used in production.