CDL again!!! Real time help please

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Hey guys have read a hundred post it feels like on this. I have been troubleshooting the cdl on the 96 I just got running. When I shift into 4l I get no lights or relay clicking sound. I have taken the sensor of t case and cleaned. When I jump the sensor I get the cdl and abs light. My question is what is the next step to get the cal to engage I have been driving around in the driveway gravel in all gears forward and reverse and the relay never click or gives me the whirling noise from the motor??
 
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I have a cdl(hazard switch I just installed also) not pin 7 mod. When I jump the harness the relay clicks and the cdl/abs light come on. I have tried tapping the actuator with Thor’s hammer and still don’t get any relay or motor sound.
 
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If you are jumping the harness side and getting the light wiring is good, so I would say your t case switch is bad if I’m understanding you correctly
 

migz808

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Did you try another hazard switch?

Don't you need to do the #7 pin removed for this to work?

Never had an issue with the CDL/7 pin mod on all the years 93-97.
 
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If you are jumping the harness side and getting the light wiring is good, so I would say your t case switch is bad if I’m understanding you correctly
So I swapped the switches on the t case and rear actuator. And no change. If I am understanding correctly the center diff has to be engaging to tell the sensor it’s working and that opens the circuit to the lights and tells the 4wd ecm it’s happy and than can engage the diff locks.
 
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Did you try another hazard switch?

Don't you need to do the #7 pin removed for this to work?

Never had an issue with the CDL/7 pin mod on all the years 93-97.
I tested the switch before installing and it’s working. I am not relying on the switch that is just a convenient install. I am really just transferring to 4l trying to get center diff to engage. And no you don’t need pin 7 mod unless you want full control of the center diff. I guess I could do pin 7 mod and see if that works.
 
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Yes you need to get the center locked for the diffs to lock. Is the center not locking correct? No light on dash no relay or noises when shifted to low? I assume you are trying this with out your hazard switch in the system? Pull the hazard switch out put the yota jumper back in. I popped a hazard switch that I found into one of my trucks and it did not work correctly
 
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If truck does not auto shift when put to low and you haven’t done the pin 7 then actuator or switch in t case is bad.
 
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You can prob also pull the t case switch put a meter to it and actuate it. Read ohms and see what you get
 
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You have checked the center diff lock indicator switch and the L4 position switch correct
 
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I did test ohms on switch and they both tested the same infinite ohms when open and under 1000 when depressed. I’m electric challenged with a meter. I believe I was doing that right. I think I might have to remove the actuator and clean up the old grease inside and relube. Just don’t wanna go that route if there is a easier way.
 
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The indicator switch is the one I swapped with the rr diff lock switch and I pulled and cleaned the l4 switch also.
You have checked the center diff lock indicator switch and the L4 position switch correct
 
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I think I’ll apply power to the actuator and see if it moves. Or loads the spring up.
 
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Sounds like switches are good if reading open when not depressed and showing continuity or a reading when pushed. Sounds like dash wiring is good when harness is jumped. This points to the motor I think. Make sure you got all your connections fully seated
 

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