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Old 11-25-2016, 04:45 PM   #1
Jsfucttruck
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91V1500 Electronic speedo to Mechanical w/Tach

[IMG][/IMG]Maybe 5 yrs ago we picked up this 91V1500 Burb with heavily equipt factory options. We saw it in Medford OR, and had to have it. It had been changed over to a 8 lug front and a full float 14 with a 6" lift and 35" Toyo's on 18" rims. For the price was fair, so we jumped on it. After 3yrs the trans started slipping so I swapped out the stock 700r4 for a friends used "built" 700r. Well long story short, it didn't work.
I really want to swap a 400/208 or a 400/205 into it and not another 700. I have a 400(round pattern)205 that I am considering having rebuilt, or just source a 400 for a 208/241 and have it rebuilt and use the stock t-case. Either way, the electronics are going to have to go too.



So I have this 81-86 Tach cluster that I want to swap in. I also have a extra electronic speedo to compre the harness. So I got some wiring to do.[IMG][/IMG]
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Old 11-25-2016, 05:05 PM   #2
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Re: 91V1500 Electronic speedo to Mechanical w/Tach

Bare with me here, I just started looking into this swap last night.


[IMG][/IMG]


After a hour of tracking down a harness plug, I started mapping all the printed circuit differences, and there are many. The choke to check engine light indicator is easy, I am having to digg a bit deeper to figure out the abs/brake warning light swap.
[IMG][/IMG]
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Old 11-25-2016, 05:14 PM   #3
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Re: 91V1500 Electronic speedo to Mechanical w/Tach

After a hour of mapping last night I realized that the extra electronic cluster that I have is from a 87 and it is wired differently than my 91. Back to the drawing board.
My 91 Cluster.
[IMG][/IMG]
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Old 11-25-2016, 05:29 PM   #4
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Re: 91V1500 Electronic speedo to Mechanical w/Tach

I 'm sure a few of you are wondering why not just fix what is there? Well, it got complicated at some point between a bad speedo replacement, and wiring to vss issue. I had a problem with the lockup converter due to the failing vss and didn't realize how important that all the systems were linked and cooked the second trans. After replacing the vss and some damaged twisted wiring I thought I had it fixed. Turns out the over run clutches(I think) are shot in the trans and it acts like it has a full cheeta valve body with no engine braking in any gear. I don't know if this was causing the speedo to function incorrectly because the speedo will work(w/lock up) when accelerating. As soon as you coast or let off the throttle a little, the speedo stops working, and the converter Un locks.
So, after two speedo swaps, vss replacement, wiring repair, and a used trans swap. I am still in the same spot with it, so I want to swap out the electronic speedo setup, abs since I have a factory mechanical tach cluster. Here we go.

I thought that tossing some parts at it was going to fix it. Easy route by-passed.
Long drawn out swap to come.
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Old 11-25-2016, 05:50 PM   #5
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Re: 91V1500 Electronic speedo to Mechanical w/Tach

So at least I have the 81-86 cluster mapped out so I dug up a wiring harness schematic for the 91. I am going to use it as a guide, but I am going to confirm every connection source.[IMG][/IMG][IMG][/IMG]
This one is from another site, sorry.
[IMG][/IMG]
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Old 11-25-2016, 06:05 PM   #6
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Re: 91V1500 Electronic speedo to Mechanical w/Tach

[IMG][/IMG]


Found lot's of good info. I got board at 1 am so I decided to at least check the lighting end of the printed circuit. I like these Phillips LEDs.[IMG][/IMG]
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Old 11-25-2016, 06:08 PM   #7
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Re: 91V1500 Electronic speedo to Mechanical w/Tach

Looks like I have to find another printed circuit harness plug. This tach cluster was for a 2wd truck and the Fourwheeler drive light and choke are blanks in the harness. I need to find 2 pin connectors, so off to the wrecking yard. 1/2 off at pick n pull this weekend. Happy hunting.
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Old 11-25-2016, 06:18 PM   #8
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Re: 91V1500 Electronic speedo to Mechanical w/Tach

These manuals have been very helpful with a number of things. Are these things out there in PDF somewhere? I would love to find a place that has these transposed. Pretty much looking for every yr from 67 to 91. Best looking yrs.[IMG][/IMG]
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Old 11-28-2016, 10:34 AM   #9
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Re: 91V1500 Electronic speedo to Mechanical w/Tach

It can be done going the other way (electric to cable) but will require re-pinning your harness plug. I went from cable to electric in this thread. Might help you out a bit:

http://ck5.com/forums/threads/conver.../#post-3086053

You'll have to keep your computer happy with a VSS pulse, cruise and rear abs (if you have them).
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Old 11-28-2016, 11:27 AM   #10
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Re: 91V1500 Electronic speedo to Mechanical w/Tach

Member hatzie has that pdf linked in his sig, he's a good source of info himself.
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Old 12-02-2016, 07:27 PM   #11
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Re: 91V1500 Electronic speedo to Mechanical w/Tach

I was seriously considering such a swap myself...until seeing what was involved. Way to technical for me.

...not to hijack your thread but I was just about to start a new one myself asking how to disconnect the electric speedo from the circuit board.

I've been tugging on that grey plug looking thing and am afraid I'm gonna do more damage then then needed. Gotta be something I need to do other then reef on it.
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