Builds 1974 Pua'a

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Gettin tired of corn teen, and not driving the pig, even though it’s over 100F every day here in ATX, and I don’t have AC or even heat right now.

Technically it’s out of registration, won’t pass inspection cause the horn doesn’t work. First things first.

So I got the pig started (all the gas was gone, maybe stolen), and pulled the pig back around into the shop.

Jumped 12V to each horn. Both work. Found the horn relay, but haven’t debugged past that yet.

“Charge” light stays on when running now. Maybe fix that next.
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OK. Bottom of the relay is marked ‘B’, ‘H’ and ‘S’.

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The horn switch in the steering wheel (connected to the ‘S’ terminal on the relay) is supposed to close the circuit to energize the coil in the relay. It completes the circuit by connecting it to ground. Power comes from the ‘B’ terminal for both the control side and the load side. Load side is marked ‘H’.

Circuit diagram
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Once the coil energizes, the relay engages and you pass 12VDC from the ‘B’ terminal to the horn terminal (‘H’).

So
• the ‘B’ terminal must have +12VDC on it.
• the ‘S’ terminal must be connected to the horn switch, which grounds, and
• the ‘H’ terminal must be connected to the horns.

Pressing the horn button should get you continuity in the socket only between ground and the one socket connector that connects to the ‘S’ post on the relay. Connectivity from the ‘H’ post has to carry 12V to the horn, and there has to be 12V to the ‘B’ terminal.

First things first. We have 12VDC with key off to one of the terminals. Lucky day; it’s ‘B’.

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Shorting (jumper) between ‘B’ and ‘H’ makes the horn sound. Two for two.

To test the horn switch (in the steering wheel, connect test light to +12VDC (positive post on battery), stick the probe in the slot that takes the relay terminal marked ‘S’, and hit the horn buttons on the steering wheel.

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Hit the horn buttons. The test light should light. I have video of this but it doesn’t want to upload on the phone. Had to down convert the video to 480p and 8fps to get it to upload, but that shouldn't be a problem for understanding what's occurring. I'm pressing each of the 3 horn buttons three times.

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So the column is wired correctly, and the socket is wired correctly. Survey says: bad relay. It does look a little punk, and the innards rattle a bit when you shake it.

Ordered off fleabay, ($50! That’s 1% of my $5000 budget!!), but it takes a week to get here from Japan. I'm in Colorado next week, so ¯\_(ツ)_/¯.
 
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Hit the horn buttons. The test light should light. I have video of this but it doesn’t want to upload on the phone.

Survey says: bad relay.
Did the test light light?
In you picture it doesn't look lit.
 
Yes. The one picture where the test light isn't lit was just to show that I stuck the probe in the 'S' socket. The test light in that picture is connected to +12VDC, and wouldn't light until someone presses the horn button. My arms aren't long enough to reach from the PS fender to the steering wheel.:p

Everything checks out except the relay, which doesn't work. I took the lid off, applied 12V to 'B', and connected 'S' to the negative post on the battery, and the coil doesn't energize.

Were they hand-winding these in Japan back in the day, or did someone try to fix it? Doesn't look machine-wound.

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Walked the dogs, wife complained that the DS mirror on her 62 shakes a bit. It's always something, right?
 
Cool stuff!
Wanna see something cooler, possibly sadder?

I had a box in my office, complete harness from SOR (unknown year), 'cause this pig needs a harness.
I've never opened the box.

So I think, "hey, I'll work on the tailgate." It's missing a couple internal pieces.
So I go fetch the box from my office, where it's been for 18 months. I open it, dig pass the harness and what do I find?

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Horn works!
 
That's awesome! My memory has gotten so bad, it seems to happen more that I want to admit. Except I order the new part before I find the one I ordered first.
 
That's awesome! My memory has gotten so bad, it seems to happen more that I want to admit. Except I order the new part before I find the one I ordered first.
I did that too. It should ship from Japan and arrive next week (while I'm in Colorado).

I even have an appointment (yeah, yup) to re-register it when I get back, assuming I can get it to pass inspection now.
 
Oddly, there is a second horn relay in the box, so now I'm flush.

on to the tailgate.

I now have the channels in each side of the tailgate. they were missing before. (Apparently I had a "parts gate".)
Yes, I know I will need to go back and replace the glass runs (rubber) in each side, but it's nearly midnight, and I don't have any of the correct adhesive in the shop.

Kinda wondering if there is a missing "pin" or "nail head" on the glass channel (bottom of the tailgate window).

Also, the little L-shaped tabs (pic copied from the "tailgate" article) ... can you buy them, or do you have to fabricate them these days?
Anyone have a drawing?

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Kinda wondering if there is a missing "pin" or "nail head" on the glass channel (bottom of the tailgate window).

Also, the little L-shaped tabs (pic copied from the "tailgate" article) ... can you buy them, or do you have to fabricate them these days?
Anyone have a drawing?

There is a pin. I have seen information in a thread somewhere on how to fabricate one but not sure where. Here is a pic of the parts with the pin in place. Can’t help you on the L shaped tabs.

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I think I’m gonna stop in Poncha Springs while I’m in Colorado next week and buy a bit more tailgate gear, and a couple other body items (door parts).
 
There is a pin. I have seen information in a thread somewhere on how to fabricate one but not sure where.
Rear window article available from Gary S







Rear window article available from Gary S







 
Swing by Idaho on the 27th and I'll fix your lower track or give you another.
That's a really kind offer, and I really appreciate it, but I don't know if I can make PP20.

I (we) have a business to run, and we're in the middle of a product re-launch.
The subject did come up at Chez Gonzo, but wasn't well-received.
 
I (we) have a business to run,
I get it, I also have a few of those and had six big projects dropped in my lap that have to be done before I can go camping with my buddies.
If anything changes on your end you are always welcome to come out and hang with us.
 

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