CDL not working. (1 Viewer)

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So I finally got aroud to putting in the CDL today and everything seemed to go well except the PIN 7 mod. For those of you who don't know...here's the instructions per C-Dan.

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.

Thought I followed this to the letter, but once everything was back together again, the CDL locks, but doesn't unlock. I tested it before the PIN 7 mod, and it seemed to work then, but everything is buttoned back up now and it's not unlocking. I did notice that there were two wires that I could have pulled in the final step. See teh picture below. There was a thinner black wire with blue tracers, and there was also a thicker blue wire with black tracers. I chose the first option, but don't know if I did right. Anyone with experience?
 
From the photo , it appears that you removed the correct wire.

Is the center diff lock switch plugged in all the way? I assume that you have added the switch, correct?. If the switch is not fully plugged it the diff will not unlock. There is a jumper in the switch that mimics the jumper plug, if that is interupted the diff will not unlock.
 
I removed the "plug" with the jumper in it and clipped in the CDL. Before I did the pin 7 mod, the CDL locked and unlocked fine while in Park in my driveway.
 
OK,

is the connector firmly plugged in to the diff lock ECU?

I have not seen this symptom before. Did you cut or remove the wire from the connector? If you removed it, you may try reinserting it in the connector and see if the unlock is restored.
 
I believe so...I buttoned everything back up, and I'm in the process of pulling it all apart again.

I pulled the plug, didn't cut it.
 
Did you tape the exposed terminal?
 
Yep,

Do you think it's in the CDL or the ECU?

Thanks for being online!!
 
Not sure,

put the wire back in the connector and see if the unlock is restored.
 
Ok, So put the pin 7 mod back, and NOTHING...drove in a straight line back and forth in the driveway and it remained locked.took the dash back apart and replaced the CDL with the "plug", turned the car on and did the same driving test. CDL UNLOCKED!!!!

What gives?

Bad CDL?
 
pps CDan- My guess for you to pass Woody was today....this may work out after all :D :D

3.5 hours and 42 posts to go.
 
>> Bad CDL? <<

That's the first place to look since it is the variable. Check pins, connectors, wires, etc. Use a multimeter to test continuity. I don't have the pin-outs for your '93 switch but they're probably in the archives on this site somewhere.
-B-
 
So I put the CDL back in and played with it a bit. Seems to work for the most part.

Question: Do I have to be in P or N to engage the CDL, or can it be done from Drive?

I can get it to work from any position from the limited testing I did out in front, but sometimes it just seems to "stick" I can hear the CDL signal the change every time it is pressed, but sometimes the CD doesn't unlock right away. I sometimes had to go to R and drive for a bit, then back to D. Sometimes it would unlock in R, sometimes not until I went back to D.

But it seems the the moment I drop it into Low Range, the CDL engages, and the moment I put it back in High, the CDL unlocks.

Any Ideas?

B- Did a search for the diagram with no luck, any hints? Or with what I just gave you do you still think it could be the CDL? I'm not as convinced anymore.

LT- You could put a toggle in, but when you see how far back in it is, you'll realize that it's really not worth it. I guess you could run extra wires to make the toggle more accessible, but it the mod is done right you'd never want to go back anyway.

Thanks for the input so far. :beer::cheers: :beer: :cheers: :beer:
 
>> but sometimes the CD doesn't unlock right away. <<

Normal. It doesn't sound like you have any problem with the CDL to me.

-B-
 
Maybe I should expound a bit.

Before starting this post, I locked the CDL and tried to unlock it and it wouldn't unlock. I drove up and down the street, Reverse and Drive, re-locked, and then tried to unlock it again. Went back and forth between H and L and didn't get anywhere. Turned the truck off and on several times and tried everything again. Everything to no result. Changed out the PIN 7 mod and did it all again. Still nothing. It was only when I put the plug back in that it fnally reset. But now it seems fine, maybe one more trip down the block would have done it last time. I guess what I'm trying to say with all this...is that it took a REALLY long time to unlock.

What physically has to happen in the CD for it to lock and unlock? Could something be fouled up there? Thanks.
 
Where is the post from c-dan on the cdl relay mod? I searched with no luck on this and the SOR baord.
 
[quote author=landtoy80 link=board=2;threadid=9037;start=msg78553#msg78553 date=1071981135]
Where is the post from c-dan on the cdl relay mod? I searched with no luck on this and the SOR baord.
[/quote]

The instruction portion is in my original post
 
It's been posted a few times so you may have to dig, but Beo gave a good hint to find the instructions awhile back by searching for the words

cigarette pack

as they appear in the instructions and not much else.
 

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