Testing trim sender.

[yockman]

Yammie gauges are giving me some grief atm. I have just bought a s/h f115. The trim gauge isn't working. Here is the info:<br />The trim mechanism itself works fine.<br />Backlight on the gauge works.<br />It's a 3-wire job. <br />All 3 wires from the connector under the cowling to the connector at the gauge show an open circuit on the multimeter.<br />When you stick the multimeter in the pins on the connector from the sender, and push the sender around on its spring, the resistance reading goes from about .3 to .9, so I guess that the sender is working (???)<br /><br />Two things I dont understand: where does the power for the gauge come from? (the wiring goes straight from the sender to the gauge, does not intersect with the loom or any other wiring. I thought it should be getting 12v from somewhere) and how can I test if the gauge itself is faulty?<br /><br />All help much appreciated,<br />Yockman

 

[bigbrownbuku]

Re: Testing trim sender.

the guages are powered from the control box. the yellow wire specifically is the 12v source. the black is the ground, the red is constant 12v and the green is the tach signal.

 

[rodbolt]

Re: Testing trim sender.

hello<br /> there are orange, pink, and black wires on a 3 wire sender. orange is a 5 v reference. black is ground and pink is the pick off voltage from the sender potentiometer. as the wiper goes from the orange feed to the black ground the voltage on the pink changes. to test check from orange to black and the while moving the arm from pink to black. remember a digital meter will not react very fast.<br /> the specs are in your service manual.<br /> good luck and keep posting

 

[yockman]

Re: Testing trim sender.

Time I got in the room full of mirrors for a good hard look at myself. <br />Fixed trim gauge and tacho problem mentioned in other thread tonight. Both simple, Wires in wrong place, despite me looking at every wire 50,000 times. All those piggyback wires in the back of those yammie gauges !@#$. Trim gauge 100% now.<br />Sorry to start a wild goose chase!<br />Cheers,<br />Yockman