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Master Switch Wiring Diagram needed


Bob R

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Bob,

The POH has the most basic, yet very complete wiring diagram for your plane...
 

After that the maintenance and service manuals probably have a more complete version...

How specific are you needing?
 

Check the download area for manuals like these...

Best regards,

-a-

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1 hour ago, Bob R said:

Does anyone have a master switch wiring diagram or a complete wiring diagram for a 1969 Mooney M20E. I'm in desperate need of one.

Bob

 

What exactly are you looking for? I have many wiring diagrams. They are kind of huge. I can snap a picture of the relevant parts. A serial number may help.

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I'm in the middle of a wiring fiasco because whoever wired the main bus bar at some point in time really screwed it up. I have replaced all the breakers with the new style Klckson breakers. However, I don't have any power to the battery terminal on the ignition switch. The only complete wiring diagram I have is from a 67 M20E which does not have the wire numbers. In addition, the master switch when I pulled it out, was completely upside down therefore off was on and on was off, not that it makes a huge difference on a DPST style switch. I have the 106 service manual, unfortunately mine does not include the complete wiring diagram on one page, but I would love to know which wires go where on the master. There is also a wire that runs off the ignition switch ground which at this point actually engages the relay back in the battery compartment. I know my starter solenoid works because I can jump and it will crank. Of course, that does not mean the starter solenoid is good. I hope this helps and any help you could provide would be greatly appreciated. I have spent countless hours on my back verifying and redoing wire connections so I know they are correct.

Thanks again,

Bob

 

 

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I can only Speak for a '67C with no avionics master. As I recall correctly for the master switch One set of contacts provides ground to main power contactor/relay I may be either 18 awg or 20 awg wire. The other set of switch contacts is for the alternator field circuit. I think it's either a 18 awg or 20 awg wire. I am  not sure what year when Mooney will went to a avionics master. An airplane goes through a lot of upgrades over the years not sure how many avionics shops  update the Airframe electrical system drawing( s) I would suspect not that many.

James '67C

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Modern Mooneys have turned the one switch into three... or four...

1) Master

2) Avionics Master, wired backwards intentionally for failure protection... (something that may require a bit of understanding)

3) Alternator... where this gets a double switch for two alternator systems...

PP thoughts only, not a mechanic...

Best regards,

-a-

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The 77 M20C POH May have some similar wiring diagrams...

Two pics...  one shows details regarding the ignition switch.... the other shows the size of the CB for the cigarette lighter...

CB... IGN CIG LT 10A

What else was needed?(as in I forgot what the request was....)

 

Hmmm...

pics aren’t loading today....
 

I’ll try a PM to the OP... see if that helps... (negative, something wrong with my pics?)

-a-

 

 

315ABB24-F268-4A50-9AC4-7120633A91DF.png

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I’m not so sure I would be blaming others. 
 

it’s a pretty simple pair of circuits. One goes to the gen field, which if you have an alternator no longer exists,  the other side feeds a relay. One side will have power and the other will have ground. 
 

the relay ties the battery to the bus bar. And the starter solenoid, which is then closed when you push in on the ignition key. 
 

it’s all in the service manual. 

Edited by chriscalandro
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