How to jumper the CDL?

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Fargo, ND
Stupid question, but I have been trying to figure out why my CDL doesn't engage. I installed a new CDL sensor (on the T case), and have read many threads that say to jumper the CDL switch? to see if the light will come on. How do I do that? Any pics anywhere? When I shift into 4L I get nothing- no sound, no lights, etc. It goes into Low but that's it. Any help is greatly appreciated. Thanks, Dan.
 
Stupid question, but I have been trying to figure out why my CDL doesn't engage. I installed a new CDL sensor (on the T case), and have read many threads that say to jumper the CDL switch? to see if the light will come on. How do I do that? Any pics anywhere? When I shift into 4L I get nothing- no sound, no lights, etc. It goes into Low but that's it. Any help is greatly appreciated. Thanks, Dan.

I believe they are talking about jumping the switch (or sensor) you replaced on the TCase.

Unplug the sensor, and jumper the wires to see if the light will come on. If it does, plug the new sensor in (while it's unscrewed) and push the end of the sensor in and see if the light goes on.

If all is good, it is safe to assume your "switch" is fine, and the CDL is not being engaged. If the light does not come on, then your CDL may be engaging but the switch or wiring needs to be addressed.
 
Unplug your Hazzard switch (if you have a 95+ plus rig) and plug it into the cdl harness in the upper dash button area. There will be a shunt plugged in. Remove it. The Hazzard switch has the same pin operation as the factory cdl switch. This way you can engage and disengage the cdl at will.
 
OK, so I jumpered the CDL sensor/switch and the lights came on, I heard the click in the kick panel, and I could hear the lockers move when I turned the dial. So, that means that my CDL is not engaging, correct? So, now I will have to possible rebuild the CDL? Thanks for the replies guys! I am excited to know that my lockers will work- I've had this rig for over a year now and they have never worked- too many other things to do first. Now if I can just get the CDL figured out, it will be awesome.

PS. The switch/sensor is new.
 
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There are two switches, the first is the 4Low sensor that gets activated when you shift to low range. It fires the signal to lock the center diff. The second switch indicates when the center actually locks. Check both switches.
 
So it is entirely possible that all I need is the switch that tells the CDL to lock then. Can I jumper that switch and see if it locks the CDL?
 
Yes, but it can be a wiring issue also. The last thing I would do is to mess with the CDL actuator.
 
I will jumper the other switch and report back. I appreciate the feedback!
 
PPC- is the 4 Low sensor on the front of the T case on the left side? I think that's what it shows in the FSM.
 
Is it one of these?



image-2117289862.jpg

image-2117289862.jpg
 
image-362211165.jpg

This is the CDL indicator jumpered.

image-362211165.jpg
 

That is a pic of the CDL indicator jumpered.

Doh!! Double post from app- sorry.
 
I can't tell much from the pictures. The L4 switch and the Neutral switch are located on the rear of the transfer. Looking towards the front the switches are at 2 o'clock and 11 o'clock positions respectively. The CDL indicator switch is on the front. You should be able to search and find some pictures. You should be able to test each one by jumpering the connectors. With the ignition on begin with jumpering the L4 switch and you should here the CDL actuator activate.

Transfer switches.jpg

Transfer switches.jpg
 
Ok, I will try looking at the correct end of the T Case tonight ;-)
 
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I've had this rig for over a year now and they have never worked- too many other things to do first.

Hope you got this all fixed, BUT, I need to formally reprimand you that this should have been done a year ago!!!! ;)
 
Any tips for getting the 4L switch out? I can't get a socket on it and there is not much room for a crescent wrench either. Any suggestions welcome!

It not because I haven't been working on the Cruiser :-)
 
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Any tips for getting the 4L switch out? I can't get a socket on it and there is not much room for a crescent wrench either. Any suggestions welcome!

It not because I haven't been working on the Cruiser :-)

I used a "shorty" crescent wrench (only about 4-5" long) on the cdl switch...
 
A visegrip worked for me. I jumpered that switch and I have the locker light!! Ordered a switch and I am in business with my newly LOCKED Cruiser! Yes! Thank you once again MUD!!
:bounce::cheers::bounce2:
 

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