Trailers and controllers and wirings and stuffs... (1 Viewer)

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Oh, while I'm thinking about it: a question on best practices for wiring.

According to the diagram, I need to create a couple of short daisy-chains in the four-relay block, where one pin connects to the next, and that one to a third, then to a fourth...so in at least one portion of that assembly - namely, the ground - I will have two wires going to one pin: do I just need to check the total cross-section of the wires and then size the connector accordingly, or is there a better way to do this?

I know I can create separate grounds, but that seems like a mess of extra wiring...and there are two other portions of the circuit that need the same treatment, where I can't just make separate feeds.

Opinions?
 
Because I teach science and math, I do as you stated: I add the 2 cross-section areas and then calculate the new diameter.

What did you cut the sheet steel with? Edges look straight and square, etc.
 
Because I teach science and math, I do as you stated: I add the 2 cross-section areas and then calculate the new diameter.

I noticed that the AWG scale is very predictable regarding cross-sections; drop three gauges and the sectional area doubles. So for 14ga - assuming this method to be correct - I should be able to use a connector for 10-12ga, as 11ga would be the perfect double. So, that's pretty easy; weather-sealing two wires in one heat-shrink tube, however...that might be fun.

What did you cut the sheet steel with? Edges look straight and square, etc.

Thank you! The cuts were done with a 5" angle grinder with a 4.5" .040" disc, with the speed turned down a bit. The rough cuts were a bit flashy and ragged; I couldn't find the discs that I've used before and prefer (Sait, or Pferd) so I had to make do with one from the local box store, and cut quality suffered a bit.

Straight cuts are pretty easy: for anything over about a 3" cut, I'll clamp a piece of scrap angle steel to the work as a cutting guide. The .040" discs don't like to bite into vertical stock - they flex instead of gouging in - so as long as you do your layout marking with the inside part of the cut line being a final-ish dimension, you can cut directly against the vertical plane of the steel and get a pretty decent line. That might be cheating, and I'm sure that there are plenty of guys and girls that can eyeball a mile-long straight line with a grinder, but I'm not them...so I'll happily cheat my way to straight lines.
 
Lots of work, today... including finding a too-good-to-be-true mounting location for the relay block.

Pictured: The mounted relay block.

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In case you're having trouble seeing it...

Pictured: C'mon...the machine screw in place of the trim cap was a dead giveaway...

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Somehow, the gods decided that an unused trim clip hole and the trim screw hole above it and to the left were the literal perfect size and location for opposite corners of the relay block's mounting feet to bolt into...and the process of bolting it in was far less awkward than this sentence.

It's so, so tempting to use this location: it's already there, it's the right size, it allows mechanical fasteners, and the trim panel snaps right over it with no protests...but it's just kind of in the wrong place. It makes the wiring longer (and I'm not sure how long the trailer harness I've ordered actually is) and the two corner mounts aren't as strong as having all four corners bolted in, and I'm concerned about bending the lower interior sheetmetal edge if I have to remove a stuck relay. So, that being the case, I think I'm going to mount the relay block back here.

Not Pictured: Jack and tool kit.

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See that area to the left of the vent? That's where we're going...and I think I'm going to go with an adhesive solution, here. I have some .250" 5052 plate, so I can cut a rectangle from that and then drill and tap some holes that the relay block can bolt to...and the plate itself can go directly to the flat portion of the exterior sheetmetal by way of a VHB tape layer. I have some stuff that should easily handle the temperature of the metal on a hot summer day - that seems to be about 135°F, for reference, as measured today with the sun directly on the panel in question for five or six hours - so it shouldn't be too difficult to get the relay block in place tomorrow. At least, that's the plan.

Oh, speaking of the relay block...

Pictured: This was fun*.

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* - Fun. A word which here means "incredibly confusing and stressful for someone who doesn't really understand the electricity-flavored things."

I feel that a capable person could have gotten this entire relay block sorted and wired in about an hour...but I am not that person. It took me...well, several hours...and I even had a giant diagram that I made that helped me keep everything completely straightforward and clear, despite my relays having a minor difference in their arrangement from the relays in the diagram from the Page 1 link.

Pictured: Admittedly, drawing the white wire baffled me for a bit.

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Fun Fact: that whiteboard is the most useful thing in the garage. $70 on Amazon, I think...and that's about the best $70 I've ever spent. Of course, it's now probably $270, but I digress: it really helped me keep everything in order... because there's no doubt that I would have screwed things up without it. And by the end of the night...

Pictured: Feelin' Hella good.

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That... actually, that isn't half-bad. It's tight underneath - like, wire-squishing tight - but it's all together, and every circuit is intact after my having poked, prodded, pushed, shoved and threatened all of the wiring loops into a semblance of compactness. Don't ask to see that picture: witchcraft may or may not have been involved, and as we all know, that kind of thing doesn't show up on film. Bottom line is this: the relays are all wired, and all of the pins are showing the proper connectivity...so unless I've bodged it entirely...

It...

Could...

Work!

< insert Gene Wilder face here >
 
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Well...this is a problem.

Pictured: The correct harness.

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So...this is the Tekonsha harness from the linked thread on Page 1. Same number of pins, but not the correct connector, and the harness wires may have to be re-pinned, anyway. So now I'm not sure what to do. I looked for a match for the factory connector and I haven't found one, so the only thing I know to do is to buy a semi-correct set of connectors (with pins) and replace everything. And if that's the case, I'm kind of screwed, because I don't know how soon that part will get here...and I'm on a deadline.

I think I'll try the junkyards tomorrow, but in the meantime: if anyone knows exactly what the factory taillight connector is - and how to order it - please let me know.
 
No luck in the graveyard, today; didn't find anything that's even close. I put in a call to Torfab; they didn't know the connector off the top of their heads - didn't expect them to - but hopefully they can find out what it is, or at least give me a cross reference. Haven't heard back from the email to Eastern Beaver that I sent a few days ago, either. Failing any helpful responses... I don't know; I may have to just find some different OEM-quality connectors and cut everything apart and install a known component. I really don't want to do that, but it's quickly becoming necessary.
 
No luck in the graveyard, today; didn't find anything that's even close. I put in a call to Torfab; they didn't know the connector off the top of their heads - didn't expect them to - but hopefully they can find out what it is, or at least give me a cross reference. Haven't heard back from the email to Eastern Beaver that I sent a few days ago, either. Failing any helpful responses... I don't know; I may have to just find some different OEM-quality connectors and cut everything apart and install a known component. I really don't want to do that, but it's quickly becoming necessary.
Oh man! Frustrating. Sorry. I'm several steps behind you still so following along closely.

Ordered a different harness (Curt 55358). Checked it out and it appears to be the same connectors as the Tekonsha/eTrailer one though. No help there. Haven't looked to see if it fits on my rig yet.

What year is your 73? JDM?
 
Oh man! Frustrating. Sorry. I'm several steps behind you still so following along closely.

Looks like this is kind of the crux of the whole thing; solve this and the rest isn't bad.

Ordered a different harness (Curt 55358). Checked it out and it appears to be the same connectors as the Tekonsha/eTrailer one though. No help there. Haven't looked to see if it fits on my rig yet.

Definitely post that outcome when you have it. 👍

What year is your 73? JDM?

'90. And yes, it is. I have the feeling that the connector is not going to be easy to find; I ordered a pile of Sumitomo 6-pins that are roughly analogous, though, so at least there's a backup plan. Really didn't want to slice the harness...

I think I'm taking a break from it for the rest of the night. I have some mod-work to do on the driver's seat hinge - let's hope I don't break it - so maybe that'll give my mind a rest.
 
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Did you run across Corsa Technic?
They have measured drawings.
Corsa
 
Did you run across Corsa Technic?
They have measured drawings.
Corsa

I did not see that one, yet...which is frustrating because I searched repeatedly with words that should've led me to them. Thanks for posting that link. Unfortunately, my connector isn't there. There are five or six that are close, but not quite on the money; if my semi-similar Sumitomo order doesn't come through - and I don't have an order confirmation for it, or anything - I may have to pick up something similar from these people...so, extra-thanks.

Meanwhile, this was an unrelated, overdue project: seat recline-stop modification.

Pictured: There's so much more room for activities.

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Factory limit on the left, modified limit on the right. This may be important, later...but not germane to this thread, so we'll leave it there with no further discussion.
 
And then, after many sacrifices were made to The Old Gods and a great wailing and gnashing of teeth had been heard throughout the land...

Eastern Beaver came through. With six or thirty additional pictures, they were able to identify the taillight connector as a Sumitomo MT Series, specifically the 6-Position 090 Special A (SPA). It can be found on this page, mixed in with a bunch of things that don't really resemble it at all.

I ordered ten of them, because reasons. Now, I'm going to go sleep in my front seat.
 
How did you modify that seat into a full on lazy boy recliner?
 
Your seats are different from mine. Newer I guess.

Eastern Beaver has helped me too along the way.
I too usually order extra sets "for later".
 
How did you modify that seat into a full on lazy boy recliner?

It's more of a dentist's chair. Like, the kind that give you headaches because you're tilted too far over...

...but to answer your question: I just modified the seat stop. There's a depressed point of metal on the base-side of the hinge that Toyota used as a stop, and all it does is create a blocking point for the upper/back side as the seat tits back; remove that point, and you get more tilt. There's also plenty of tilt-gear engagement still remaining as you go further backwards, but the design of the hinge is such that you can actually go past the maximum engagement point of the gear teeth without issue; I can push the seat back almost to the floor, now, but the position shown is about as far down as it will go with gear engagement. It looks like a lot of metal to remove, but literally none of it is structural, so there's a negligible impact on the seat as a whole.

I can take some pictures and put more info into another thread if people are interested.
 
Your seats are different from mine. Newer I guess.

Could be the trim level as well. These are similar to the Prado seats; hinges are identical as well, except for some additional fold-and-tumble parts.

Eastern Beaver has helped me too along the way.
I too usually order extra sets "for later".

Yep. When I moved, I bought a large cabinet with many tiny bins in it, just for situations like this. I won't be caught without these again in the future.
 
Curious if it's a difference in years or models. FJ73Texas used that same harness on his 93 HZJ77. Thought I had seen a later model wagon also use it in another thread I can't find now. Should have time tonight to open up my '97 HZJ73 to take a look. Otherwise I'll be placing an order with the Eager Beaver too.
 
Ah, that's better.

Pictured: I've been watching too much Binky.

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The frayed loom ends annoy me; I'll fix that in a bit. In the meantime: more relay block shots, because this actually turned out better than I thought it would.

Pictured: It's not so terrible.

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I did a bit of a bevel on the edges to hide the presence of an existing pressure-bevel that came from a shear, which I didn't think about when I rough-cut the backing plate. Oh, speaking of that, I don't think I posted this picture...

Pictured: Cheating.

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That's how I cut things with a grinder; I'm not very good with one, so I need all the help I can get. In fact, I'm not very good with cutting anything, so I just take my time and try not to suck it up...and that usually works. Even the mounting tape did did pretty well.

Pictured: Yay, fillets.

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I didn't perfectly round them; that's not easy with 3M tapes. If you touch them the wrong way, they become an indelible part of your body...so I try not to do that. Just a clip for clearance; the vertical pattern is to help with convection in case the body panels sweat a bit on the inside. 7" of tape should be enough; that'll hold plenty of weight, and it's not so much that it got in the way of me managing to put the block in the correct place.

Pictured: Nicely hidden.

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Yep, those ends annoy me; those are gonna get taped and cable-tied...as will the unsecured wires. So...time to fix all of that: a 5/64" Allen with a long shank works well for shoving adhesive clips into tight spaces.

Pro Tip: Use the expensive ones that you said you'd never, ever, EVER misuse..

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That's where we are right now. I'm waiting on some 1/4" braided loom to show up, so I can move on with things. More updates later.
 
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