I’m looking for an idea.
The display on my left tank jumps when half stand (23 gallons) permanently to 10-14 gallons.
I’ve been watching this for 2 years. With security almost certainly the resistance on the level meter is defective at this point.
Has anyone ever tried to repair this?
Thomas
The circuit diagram of one version of the Socata gauge cluster is
so someone good at electronics should be able to test the meter movement itself, or replace some of the other components. I think the fuel gauges are the two meters on the bottom.
The fault could also be elsewhere. What S/N is your aircraft?
I don’t understand “With security almost certainly the resistance on the level meter is defective at this point”.
The above circuit is from some internal Socata document, not the official IPC/MM, and if anybody can get hold of that secret doc it would be a huge help to all of us. That gauge cluster is now over 3k and is about to become unavailable.
Peter wrote:
I don’t understand “With security almost certainly the resistance on the level meter is defective at this point”.
I take it to mean that he is certain that the potentiometer is defective at the point of its movement where the jump occurs. (And presumably all the way to the empty tank position.)
Right; in that case the sensor needs to be changed.
But that’s a big job; I would still verify the indicator isn’t sticky.
Hi Peter, Hi Airbore Again, thanks for joining. I was hoping it would be something else. But it occurs always at the same point.
Is the tank full ( 43 Gals) everything is fine. At 23 gals the indication is jumping to 15 Gals and back again. At this point must be a connection fault.
Peter is right it is a big job. A dealer in France wants 1000 € for a used part. My hope is that I can fix it by myself or I could get a not so expensive.
I look forward to further information.
Thomas
It may not be the sensor. It could be the indicator. That’s why the indicator should be tested, by applying a suitable signal to the instrument. I would guess those meter are perhaps 100 microamps full scale. Somewhere else will be a series resistor…
The indicator is a FL 100.
I could swap the wires orange and yellow. Than I would have the error at other side.
This is impossible to help with. You need to find an electronics engineer who can read a circuit diagram. Maybe try some local community social media group.
“FL100” means nothing. The indicator is a moving coil meter (also called d’arsonval) made by some obscure French company which probably disappeared years ago. Consequently most Socata part numbers google to nothing. A French person may have luck with French google but very little stuff from 20 years ago remains online (on search engines).
This stuff is trivial to troubleshoot.
