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Old 10-08-2021, 07:13 PM
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jrock836 jrock836 is offline
Join Date: Nov 2020
Location: Burleson, Texas
Posts: 329
Default Trim Indicator Not Indicating

I'm try to troubleshoot why my trim indication isn't working. It stays planted at the bottom of the display. The servo still works. I have looked at all of the connections and plugged in / unplugged all three of the wires responsible for indicating the position of the trim servo and everything seems clean and secure. My trim servo is the Ray Allen ES MSTS-T3-7A-2 unit.

I do show 5 volts on white/blue wire coming from the EFIS.
As I understand it the two white wires 31/32 is just switched power to the servo to make it move each way. If that's the case, the only other wires to be concerned with would be the whi/grn (4) position wire and whi/orange (25) grnd wire. The (25) ground wire does show continuity to ground. Not sure how I should test the position (4) white/green wire.. Is there a voltage out of the servo I should be looking for? I'm showing about 1.4 volts which will vary as I move the trim up and dow..

Edit.. Nevermind.. I figured out the problem..

Apparently somewhere between the tail and the front fuselage harness, the grn/whi #4 wire is broken.. No continuity.. ugggg...
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Last edited by jrock836 : 10-08-2021 at 09:42 PM.