Question about gma 340 and kx 155 install

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comancheflyer30

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I'm building a harness for gma 340 and two kx 155's and confused about something.

In reference to lighting, what does connect pin 6 and 7 to high side of bus and connect pin 5 to low side of bus mean?

I know the high side means 14v but does the low side mean send the wire to ground or dimmer?

Also, I noticed that in the wiring interconnect diagram for kx155 to ki209 there is a little "P" letter with an arrow pointing to a couple of the shielded connections. What does the P stand for or mean?

It looks like King calls for both sides of the shielded connections between radio and cdi to be grounded in the diagram. Everything I've researched says only ground shield at the source end (gma 340 or kx155 when connected to ki209)
 
KX-155 or KX-155A?
 
Also, i noticed the ki209 pins need a burndy hytool but there are many different dies to choose from. Does anyone know which die is needed to crimp the female barrel connectors?
 
comancheflyer30 said:
I'm building a harness for gma 340 and two kx 155's and confused about something.

In reference to lighting, what does connect pin 6 and 7 to high side of bus and connect pin 5 to low side of bus mean?

I know the high side means 14v but does the low side mean send the wire to ground or dimmer?

Can probably hook 6&7 to dimmer output and 5 to ground or 6&7 to +12 bus and 5 to the dimmer. Depending on how the dimmer operates will determine on which is correct.

Also, I noticed that in the wiring interconnect diagram for kx155 to ki209 there is a little "P" letter with an arrow pointing to a couple of the shielded connections. What does the P stand for or mean?
Pair is my guess. There is a T in the same places for triple twisted shielded cables on other drawings.

It looks like King calls for both sides of the shielded connections between radio and cdi to be grounded in the diagram.
One is used for audio signal shielding the other is not.
Everything I've researched says only ground shield at the source end (gma 340 or kx155 when connected to ki209)
Click to expand...
 
comancheflyer30 said:
Also, i noticed the ki209 pins need a burndy hytool but there are many different dies to choose from. Does anyone know which die is needed to crimp the female barrel connectors?
Click to expand...

Pretty sure those contacts are nothing more than molex formed open barrel contacts of the .093 variety.
 

The reply that one is for audio shielding and other is not makes total sense now.

Im not sure if its a regular molex crimper. I am ordering one of those for the new kx 155 connector pins though.
 
Also, I noticed that in the wiring interconnect diagram for kx155 to ki209 there is a little "P" letter with an arrow pointing to a couple of the shielded connections. What does the P stand for or mean?
Click to expand...

The "P" is for twisted pair. It comes from the IEEE Std 315-1975 spec.

It looks like King calls for both sides of the shielded connections between radio and cdi to be grounded in the diagram. Everything I've researched says only ground shield at the source end (gma 340 or kx155 when connected to ki209)
Click to expand...

Shield both ends. The double end shielding and the twisted pair cable provided the noise immunity required for the low level / high impedance signal between the Nav/Com and the indicator.
 
Bnt... i was looking over the old harness and determined that pin 5 was looped back into pin 1 so i guess it was grounded before. Radios had been in a C182. Now they are going in late 1974 C172M.

I plan on installing all new wires and connectors. Looks like the nav hi wire from main conn must have stopped working in the past and a separate single line was run by a previous shop. That may be a good indicator to go on and redo the whole thing with new pins and wires.
 
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