Dead Glideslope needle

We've got a dead glideslope needle on our #1 indicator. (KI-209 driven by a
KX155 12v) GS flag works, needle stays centered.

I dug through our log books and noticed that this also happened in 2002 and
was repaired by "repair to aircraft wiring". I contacted the avionics shop
that did the work and they looked up the repair order. They repeated that
the GS needle was inop and the unit bench tested good and that a wiring
repair was done on the aircraft.

I've haven't seen the back side of a 209 or a KX155. The avionics tech that
previously repaired it says " it could be any or all of the 4 wires that
connect the +/- GS flag or the needle"

Can someone explain the wiring?

Thanks,
Jim Burns

Thanks.
I found the pin out for it. All 4 GS pins run vertical on the left side of
the connector. Now I've got a place to start looking.
Jim

"Aaron Coolidge" wrote in message
...
Jim Burns wrote:
: We've got a dead glideslope needle on our #1 indicator. (KI-209 driven
by a
: KX155 12v) GS flag works, needle stays centered.

: Can someone explain the wiring?

The signal from the KX155 is a small voltage (current? I can't
remember...)
that drives the needle up or down. This comes over a pair of dedicated
wires. I can look the specific pins up, but I don't have that data handy.
A separate pair of wires drives the GS flag.
The GS needle in the KI209 is just a voltmeter and probably will last
until the cows come home - the same is not true of the VOR/LOC.
--
Aaron C.

Go to http://www.aeroelectric.com/Installation_Data they have the pinouts
You can check the continuity of the wires yourself. It will be a lot easire
if you can borrow a couple of pins to connect your meter with. Of course
the easiest way to troubleshoot is to swap.

Mike
MU-2

Mike
MU-2


"Jim Burns" wrote in message
...
We've got a dead glideslope needle on our #1 indicator. (KI-209 driven by
a
KX155 12v) GS flag works, needle stays centered.

I dug through our log books and noticed that this also happened in 2002
and
was repaired by "repair to aircraft wiring". I contacted the avionics
shop
that did the work and they looked up the repair order. They repeated that
the GS needle was inop and the unit bench tested good and that a wiring
repair was done on the aircraft.

I've haven't seen the back side of a 209 or a KX155. The avionics tech
that
previously repaired it says " it could be any or all of the 4 wires that
connect the +/- GS flag or the needle"

Can someone explain the wiring?

Thanks,
Jim Burns

Thanks Mike,
That's exactly where I found the pin outs and you echoed my plan of attack.
Our other indicator is also a KI 209 so I was going to swap the connectors
to see if it follows over to the other indicator.
Jim