Electric Trim failure

[ghovey]

The electric trim on my Ovation works fine on the ground, works fine in autopilot mode (for climb or descent or altitude hold), but in the air the electric trim switch will not activate the trim, either up or down. Back on the ground the trim works immediately, in the air it doesn't matter if the gear is up or down. Any ideas, I am wondering if there is a grounding issue. 

[FBCK]

I have the same problem on my 231, autopilot is fine with up and down trims, but when I use the trim switch nothing happens, the swicth works because on the ground when I use it wih the engine off I hear it activate.  Some suggested the joint inthe tale was not properly lubed, they where correct, so I greased it up and went for a flight, but nothing really changed.  I find the prb\oblem is a lot worse in could weather, -15c, the trim wheen will hardly move as well.

[ghovey]

Well if I figure it out I will post the diagnosis. 

[ghovey]

Broken wire in the yoke wiring harness

[pjsny78]

i had the same problem with my "J". you may have a different auto pilot than myne (KFC 150) but what i did to fix the problem is simply pull out the autopilot cpu and plug it back in. fixed the problem permanently. this was reccomended by my avionics shop.

[orangemtl]

I have the same problem, only it's typically on the ground that I notice it. Comes and goes.

[sreid]

Quote: orangemtl

I have the same problem, only it's typically on the ground that I notice it. Comes and goes.

[Cabanaboy]

Today (Sat) after disengaging my autopilot, put the flaps down went to adjust trim and  electric trim was very slow and heavy control pressure, i thought it was not working because used to move much faster. On the ground i saw it move but really slow on the panel display.

[jetdriven]

lube the jack screw

[HerbC]

I have an M20R and have had both trim servos "repaired" by STEC in 2 yrs. (one of them for the second time last week). Yoke mount trim doesn't work at all but appears to be operating in autopilot (so long as its making only minor adjustments). This is a frustrating problem and now an expensive one (last week's "repair" invoice from STEC was $990). Any advice appreciated...

[Robg]

I had this exact same problem in my Bravo.  Trim worked ok on the ground, but would stiffen up at altitude, and when really cold, would freeze up and the trim wheel would not move at all, either manually or with the electric trim.  The thrust bearing was bad and required replacement.  If I recall this was a King part number.

[ndesai]

I had some concern on my Pitch trim, works fine on ground and preflight but had ocassional no response on approach and had to manually trim up. I was advised to see if the manual trim wheel is turning while using electric trim and a noticable pitch change  - too much distraction on short final but my problem got fixed with Avionics switch turned off and on - that is the CB in Acclaim. Apparently there is a clutch that needs periodic adjustments on the mechanism for the trimming or it can be a servo issue. My probelm seem to have resolved (hopefully for a while). The G 1000 has a display for trim position that I beleive accurately reflects the actual trimming based on sensors(?).     

[ndesai]

There is a SB issued today apparently, not sure if this problems are related

[ghovey]

The Avionics Shop just replaced the electric trim switch and also reran the wire through the Yoke.  They think it is solved.