pin 7 modification (1 Viewer)

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I searched with only one result. It was about as clear as mud. Just installed the CDL switch on my 95. Works great. Someone here suggested the pin 7 modification, and i'm curious as to what that does. ???
 
Advanced Search for "cigarette pack" author=CruiserDan. :D

-B-
 
Remove the dead pedal and the left front sill plate. In the left kick panel you will find a Silver metal box. That is the ABS ECU. Remove it, and behind you will find a black plastic relay about the size of a cigarette pack. It says "transmission control relay" on it. That's what you are after. The EWD calls it the "center diff lock relay", same thing. Unplug the harness from it and take a terminal pick and remove the black wire with blue tracer from pin#7. Insulate the bare terminal to suit and then put everything else back where you found it. If you have the low 4 position swith at the transfer case unplugged, crawl under there and reconnect that as well.
What you have just accomplished is you have interrupted the signal from the transfer case that tells the lock ECU that you went to low range but you are still sending a signal to the transmission ECU telling it that you ARE in low range. Therefore the transmission will shift in the correct low range pattern. In addition you now have true manual control over center diff locking. It only locks when you tell it to without regard to transfer range selection.
Oh, I forgot the final step......Grab yerself a congratulatory #6 (but not an English one as you have just performed an electrical task, sorry Jim)
 
Ah yes,

I have been quoted above.
 
Where can I find a "terminal pick"?? Is this a specialized tool or something you fab up?
 
I got mine from OTC. Snap-on probably has them. It looks something like a small flat blade screwdriver but is made of spring steel. It is cut so that there is a "blade" that is used to release the terminals from the connector cavities without damage to either part.
 
[quote author=cruiserdan link=board=2;threadid=10019;start=msg89089#msg89089 date=1073944564]
Ah yes,

I have been quoted above.
[/quote]

Dan,

they won't forget you !!!

Mike
 
Dan talked me through this one on the phone. I did not have a terminal pick and just cut the wire far enough back so that I could reattach it if I messed up. I have been using this mod a lot up here in Provo now that the roads get snowy every so often.

I even got to go play in the mountains this last weekend and exercise my lockers for the first time in awhile. It still works great Dan. I still owe you that chocolate milk. :D
 
I still owe you that chocolate milk.


Since Dan has to share everything with the dog to make friends again, you should forget about the milk and think about a bone :D

Mike
 
So then what is the difference between the "pin 7" mod, and running with the Slee CDL switch? I disconnected the plug at the t-case, and can now manually control my central diff lock, whether in hi or low range. What am I missing here?
Thx
 
Boom

The "Pin 7" modification allows the transmission to shift according to the OEM shift program. When you engage the CDL you still get the factory shift points.

With the plug disconnected, and the CDL engaged the shift point pattern is slightly different i low range.
 
Boom,

You lost your shift points in Low. Plug your plug back in and do this for the real thing.
 
Dang you Hog. 10 seconds faster than me.

Lime kitty is pissed now! :D
 
Down Kitty......................
 
Thanks for the clarification. Is the difference in shift points significant? And in what way is it a benefit off-road? Not trying to be pissy, just want to see where to fit this into my "must do" list. Oh yeah...how many :banana:'s?
Thx again,
John
 
John,
Quit whinning and do the mod. It's 1/2 banana.

Not that you need more reasons than the low range shift points while in low range, but there is another reason and that is so the plug on the transfer isn't dangling in the breeze and the recepticle on the transfer case is catching mud, bug guts, and road salt.

-B-
(I can't understand why people are so reluctant to do a 30 minute job.... and I'm slooooow.)
 
Down -B-
 
I stil like the idea of cutting the #7 wire and putting a toggle switch on it so you can have both shift pionts in Low.
Any reason why this shouldn't be done?
 
You wouldn't put the switch on that wire. You would have to put it into the wire that goes to the electronic controlled transmission ECU in 93/94 models and to the engine ECU in 95 up. The pin 7 wire controls the automatic locking feature. Pulling the plug at the transfer is what effected the shift points.
 

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