Anyone have a wiring diagram for a Cherokee 140?

paflyer

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Landed a couple nights ago and realized the nose landing light was kaput. The bulb was replaced not too many hours ago, so I figured it was infant mortality. Took it off, disconnected, no voltage on the terminals. OK, so now I'm looking at a switch, maybe a bad CB (the one in the panel is not popped), anything else? Is there a relay in the circuit? Both wires run back to the instrument panel.

The "diagram" in the POH is microscopic and about a 10th generation copy so it's basically unusable. Anyone have one they can post or PM?

Thanks-
 
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Damn, that was two airplanes ago. Let me see if I still have my maintenance, and parts manuals. I know I have them, I just don't remember where they are!
 
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Soon as I get back to the house, will send all sorts of good stuff relating to the headlight.
 
Thanks gents (and lady)!
 
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Very simple circuit with no relays. If you have pwr at the back of the switch, check the wiring fwd of the firewall. Mine had a very funky knife connector some dipskit (that's the polite way to say it) put on it that would come loose once in a while.
So anyway, trace the power either fwd or backwards. You are bound to find the break in the flow.
Good luck and let us know what you find.
 
Very simple circuit with no relays. If you have pwr at the back of the switch, check the wiring fwd of the firewall. Mine had a very funky knife connector some dipskit (that's the polite way to say it) put on it that would come loose once in a while.
So anyway, trace the power either fwd or backwards. You are bound to find the break in the flow.
Good luck and let us know what you find.

Well, lots of dipskits in the world. Knife Splice or Handshake connectors are somewhat of a standard due to their design not to come loose when the wires get pulled:

knife_splice_2.jpg


But, one must properly secure them after connecting to reap the benefits of the design (heat shrink, or plastic tubing with a zip tie centered on the connection, for example).
 
Very simple circuit with no relays. If you have pwr at the back of the switch, check the wiring fwd of the firewall. Mine had a very funky knife connector some dipskit (that's the polite way to say it) put on it that would come loose once in a while.
So anyway, trace the power either fwd or backwards. You are bound to find the break in the flow.
Good luck and let us know what you find.

That dipskit was probably employed by Piper.
 
I learned a new thing today, thank you, gentlemen.
So there was definitely a dipstick involved who forgot/failed/didn't bother to put on an insulating sleeve or even a zip-tie. :)

Back to the original problem: OP, let us know what you find!
 
I learned a new thing today, thank you, gentlemen.
So there was definitely a dipstick involved who forgot/failed/didn't bother to put on an insulating sleeve or even a zip-tie. :)

Back to the original problem: OP, let us know what you find!

Or someone cut it to troubleshoot that wire or move it to get to something else, and forgot to put it back.
 
I learned a new thing today, thank you, gentlemen.
So there was definitely a dipstick involved who forgot/failed/didn't bother to put on an insulating sleeve or even a zip-tie. :)

Back to the original problem: OP, let us know what you find!
They actually used string instead of shrink or tube/tie. It is sorta weird the first time....
 
Very simple circuit with no relays. If you have pwr at the back of the switch, check the wiring fwd of the firewall. Mine had a very funky knife connector some dipskit (that's the polite way to say it) put on it that would come loose once in a while.
So anyway, trace the power either fwd or backwards. You are bound to find the break in the flow.
Good luck and let us know what you find.
Well, A&P found a Molex connector to the bulb, that allows the front cowling to be dropped, was funky (it's under the engine so I couldn't see it without dropping the cowl); replaced, all is well.

Thanks to Blanche for the drawings. Murph gets an extra Milkbone, on me!
 
Ooh. Taking me back to my telecom days. AT&T and their freaking waxed string everywhere...
Hey, lacing is a lost art. I used to know how to do it, but it's been decades...
 
Lacing is the preferred method of securing wiring, especially in an engine compartment. Ty-wraps are prone to hardening and loosening in high temp areas, such as an engine compartment.
 
Ooh. Taking me back to my telecom days. AT&T and their freaking waxed string everywhere...

The good old days, with a Lucent 5ESS, fingerless gloves, waxed twine, and miles of cable racks! :D
 
The good old days, with a Lucent 5ESS, fingerless gloves, waxed twine, and miles of cable racks! :D

LOL yeah. We got a national level engineering exemption in writing that our racks didn't have to have waxed string in them (delivered as a completed unit to the CO - and that's how I learned how much it costs to bolt a wooden crate around a rack and how big it can be to fit on a FexEx flight... hahaha... yup... we FedEx'd entire racks of gear...) and guess what the union guys did when we showed up to install them?

Cut every single tie wrap out on their own and re-did all of them on overtime, claiming the tie wraps were a safety issue. LOL LOL LOL.

The executive VP that got our exemption was fit to be tied (pun intended) but gave up and just budgeted to let them do it at every site.

We didn't care. We delivered every single one of them, as ordered, with a copy of the exemption attached, to every site. "Sign here for delivery, please..."

Still wasn't as funny as the NYNEX guy who literally set the phone I called him on, down on a table in the CO during a major outage that HE caused... saying he was going to go take his one hour union coffee break. In the middle of the outage. Hahaha.

There was also the time a 350 lb executive VP of a bank came flying across the room faster than any NFL wide receiver and about tackled me for thinking I could open one of our crates and get to work installing his stuff in Cincinnati. I'm standing there with my snips about to cut the bands off the thing and get to work just like anywhere else.

Nobody had warned me they were a Teamsters shop.

I just wanted to get something done that day. We didn't.

I left and went and watched an afternoon baseball game and charged him for every hour I sat there doing nothing but drinking beer and eating peanuts. Whoever had that important union job to cut four bands off a crate and slide the gear three feet into position on the floor of the bank's data center, apparently did it overnight.

THAT silliness... I definitely don't miss in telecom. NYNEX is gone, that bank is gone, and AT&T is forever... so I guess I don't have to not give names anymore, but I won't. They were all interesting customers.

Of course non-union shops had their problems too. We'd been shipping stuff to Verizon for a while when someone noticed the racks in their photos weren't ours.

So next visit my boss at the time goes with another FE on-site and literally finds out they we're buying fully-racked gear from us, trucking it to the sites, and then some rack standard had changed, so their guys would unrack it all, put it in their racks, and put our racks out back in the dumpster.

Once we let the group know that was buying the stuff and reminded them they were paying for rack and stack... amazingly the next order was for all the gear to just be boxed up. LOL.

The waste of time and money in telecom doesn't touch the waste of time and money we saw in our government contracts, but it was trying hard to keep up!
 
I hear ya...money flying away everywhere.

Back around 1989 I took a crew to Atlanta to demo out a CO on the 34th floor of Peachtree Tower. I filled up two 30 cy dumpsters with 25 pair cable from the DACS, and the DC plant yielded 2 tons of 1000 KCMIL cable.

The funniest thing there was a reel of 900 pair cable. The wooden reel was 5' tall, there must have been 300' of cable on it. The end of the cable was still secured by the factory staples, not an inch of it had been used.

But the best part was the FedEx labels all over the reel. Someone paid to have it overnighted there. I have no idea how they got it into the CO. :D

I ran into unions too. At the GM tech facility in Warren, MI we were supposed to take out five 96 cell strings of pretty damn big C&D batteries after a CO was moved. Each jar held about 12 gallons of electrolyte, they were damn heavy.

About ten minutes after we started the UAW guys showed up raising hell, saying it was their work. I just grinned and told em that was fine with me.

They lasted less than four hours before giving up. :D
 
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But the funniest thing there was a reel of 900 pair cable. The wooden reel was 5' tall, there must have been 300' of cable on it. The end of the cable was still secured by the factory staples, not an inch of it had been used.

But the best part was the FedEx labels all over the reel. Someone paid to have it overnighted there. I have no idea how they got it into the CO. :D

Holy hell. 900 pair?! Hahaha. Wow. That's massive.

Have heard some interesting stories about NYSE. Basically there's never enough down-time to rip out old cabling, what with the possible damage to other active cabling and losses of possibly millions of dollars an hour even just for the circuits that are damaged, so they just keep cramming more and more cable into the building never pulling out the old stuff. And burying the old stuff so it can't get removed.

Not just telecom, the building low voltage plant for Ethernet, all of it. Total mess I hear. Our poor FE from NJ had to deal with that crap. And Manhattan for the most part.

It's common in a lot of old buildings but apparently it got to a point at NYSE that they had to have a structural load analysis done on the building quite some time ago for all the added weight.

The old "telco hotel" where a bunch of our stuff was at 60 Hudson St wasn't exactly pretty, either.

The things we used to do to have a massive number block in the 212 area code ... LOL.

I still remember our NJ FE saying he hiked blocks and blocks with a luggage dolly back and forth with gear to assemble one of our two-rack systems (small at the time) in Manhattan. Haha.

Lugged it all from his personal white cargo van he used for such silliness. Said a couple of hundreds in his pocket for bribes, a few orange cones, and an unmarked white van back then were the "way to get things done". I suppose that's not quite as safe to do these days... haha.
 
I'm losing my memory of places like 60 Hudson, 50 Newark St., McCormick Place, etc.

I just turned 60, and it was 25 years ago I walked into the first data center on earth that had a 1 terabyte data storage system. The room was around 10,000 SF, and it was full of IBM 3390 DASD.

Now you can buy a flash drive with that amount of storage. Crazy!
 
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