New here and with a question (1 Viewer)

[Woody94]

Brand new here, thanks for having me.
Before I ask this question, I have looked into this topic on here but really didn't find an answer.....as well as I'm no electrician.
94 LC
I went ahead and did the 7 pin mod for my CDL.
I followed the directions to a tee then went back over them 3 times to make sure.
The dash switch still does not engage the CDL. Nor is there a light on the dash.
I unplugged the plug from the t case and jumped the plug with a paper clip and the dash light worked fine. I replaced the actuator down there as well, but still did not engage.
I then tested the dash CDL switch plugged into the ECT harness and it worked fine for the ECT.
So the switch is good.
It does go into 4L manually just fine, but again, no dash light.
I tested the transmission relay box as well and it is good. Also checked the CDL dash switch harness and it seems to be fine .
Very confused on what the problem could be.
Thanks for any help in advance.

 

[OffRoadScott]

Brand new here, thanks for having me.
Before I ask this question, I have looked into this topic on here but really didn't find an answer.....as well as I'm no electrician.
94 LC
I went ahead and did the 7 pin mod for my CDL.
I followed the directions to a tee then went back over them 3 times to make sure.
The dash switch still does not engage the CDL. Nor is there a light on the dash.
I unplugged the plug from the t case and jumped the plug with a paper clip and the dash light worked fine. I replaced the actuator down there as well, but still did not engage.
I then tested the dash CDL switch plugged into the ECT harness and it worked fine for the ECT.
So the switch is good.
It does go into 4L manually just fine, but again, no dash light.
I tested the transmission relay box as well and it is good. Also checked the CDL dash switch harness and it seems to be fine .
Very confused on what the problem could be.
Thanks for any help in advance.

I am assuming you put the transmission into neutral? Every time I lock mine I put it in neutral but park would/should be fine as well.

Have you checked the center diff lock, indicator switch?

 

[Woody94]

I am assuming you put the transmission into neutral? Every time I lock mine I put it in neutral but park would/should be fine as well.

Have you checked the center diff lock, indicator switch?

Yes, I put it in N every time.
If you are speaking of the indicator switch underneath the vehicle, on the top corner of the t case, I actually replaced it today just to be safe and paper clip jumped the plug, which actually turned on the diff lock light on the dash

 

[Woody94]

Yes, I put it in N every time.
If you are speaking of the indicator switch underneath the vehicle, on the top corner of the t case, I actually replaced it today just to be safe and paper clip jumped the plug, which actually turned on the diff lock light on the dash

I'm stumped

 

[ppc]

I went ahead and did the 7 pin mod for my CDL.
I followed the directions to a tee then went back over them 3 times to make sure.
The dash switch still does not engage the CDL. Nor is there a light on the dash.

The "pin 7" mod is not relevant to your situation. The only thing that mod does is to eliminated the automatic locking when switching into 4-LOW. It can also impact the shift points of the transmission but that's a different discussion not something you need to address with your problem.

You haven't been very descriptive as to how you are testing and determining it not working.

Was the CDL working properly before you started making changes?
Are you using a real OEM CDL switch or a repurposed 4-way flasher or similar.

When everything is working properly, when trying to activate CDL by the dash switch or shifting to low range You should hear relays clicking. You have not indicated that is occurring. If you don't hear that, are you testing with the ignition on without starting the engine.

To start I would remove the switch and reinstall the factory jumper where the CDL is plugged into. That is going to be the simplest path to keep things as simple. Depending on replies to my question, I would suggest testing the 4-LOW Position Switch, jump the connector like you did before.

 

[Rusty Marlin]

I am assuming you put the transmission into neutral? Every time I lock mine I put it in neutral but park would/should be fine as well.

Have you checked the center diff lock, indicator switch?

Are you talking about locking the T-CASE into Low or the locking the Center Diff?
The center diff can be locked with the CDL button at any time and speed as long as there isn't relative motion between the drive line outputs. I lock/unlock mine at speed as I enter and exit the soft sand roads around here frequently.

@Woody94 , welcome to group. Mine just worked when I followed the instructions, sorry I'm not much help with this one.

 

[Woody94]

The "pin 7" mod is not relevant to your situation. The only thing that mod does is to eliminated the automatic locking when switching into 4-LOW. It can also impact the shift points of the transmission but that's a different discussion not something you need to address with your problem.

You haven't been very descriptive as to how you are testing and determining it not working.

Was the CDL working properly before you started making changes?
Are you using a real OEM CDL switch or a repurposed 4-way flasher or similar.

When everything is working properly, when trying to activate CDL by the dash switch or shifting to low range You should hear relays clicking. You have not indicated that is occurring. If you don't hear that, are you testing with the ignition on without starting the engine.

To start I would remove the switch and reinstall the factory jumper where the CDL is plugged into. That is going to be the simplest path to keep things as simple. Depending on replies to my question, I would suggest testing the 4-LOW Position Switch, jump the connector like you did before.

The CDL light was not working before I made changes.
It is an OEM CDL switch that I am using
I think I hear a clicking? But cannot state that as a fact do to being deaf in one ear.

 

[ppc]

The CDL light was not working before I made changes.
It is an OEM CDL switch that I am using
I think I hear a clicking? But cannot state that as a fact do to being deaf in one ear.

The sounds of the relays are going to be important. That's why I suggested not having the motor running. With your hearing loss then get a wife, kid, neighbor to be your ears.

In your first post you stated:
I unplugged the plug from the t case and jumped the plug with a paper clip and the dash light worked fine. I replaced the actuator down there as well, but still did not engage.

Did you replace the actual CDL actuator on top of the transfer case or was that just the CDL sensor switch that is located in the front of the transfer case near the front driveshaft?

Next steps if you do hear the relays is to determine that the front/rear are locked by putting the vehicle up on jack stands and see how the axles move relative to each other.

 

[Woody94]

The sounds of the relays are going to be important. That's why I suggested not having the motor running. With your hearing loss then get a wife, kid, neighbor to be your ears.

In your first post you stated:
I unplugged the plug from the t case and jumped the plug with a paper clip and the dash light worked fine. I replaced the actuator down there as well, but still did not engage.

Did you replace the actual CDL actuator on top of the transfer case or was that just the CDL sensor switch that is located in the front of the transfer case near the front driveshaft?

Next steps if you do hear the relays is to determine that the front/rear are locked by putting the vehicle up on jack stands and see how the axles move relative to each other.

I turned the key to accessory mode today and can hear the relay working.
I did not replace the actuator itself, only the CDL sensor.
I appreciate the advice. I will put it on jack stands tomorrow and rotate the tire to see what's happening.
I do know that if I use the stick and manually put it in 4L it engages. Tried it in a patch of dirt and did figure 8's

 

[ppc]

I do know that if I use the stick and manually put it in 4L it engages. Tried it in a patch of dirt and did figure 8's

Shifting into low range is a mechanical function, not electrical and not related to the CDL activation other than the 4LOW sensor switch.
If you search the forum there may be one hundred threads with your specific issue.

 

[Broski]

Are you talking about locking the T-CASE into Low or the locking the Center Diff?
The center diff can be locked with the CDL button at any time and speed as long as there isn't relative motion between the drive line outputs. I lock/unlock mine at speed as I enter and exit the soft sand roads around here frequently.

^^^^ This, I lock and unlock mine in gear moving, stoped or in neutral.

 

[Broski]

I’m thinking the light in your dash is out.

Doing figure eights is for the axle locks.
Should not be necessary for the CDL same with putting it up on jack stands.

 

[ppc]

I’m thinking the light in your dash is out.

He already stated in the first post that he shorted the pins in the connector on got the dash light to illuminate.

 

[thatcabledude]

The connector on the indicator switch on the t-case could be damaged or unplugged. The switch itself (on the t-case) could be bad. It will not prevent anything from working properly except the light on your dash.

 

[Woody94]

Shifting into low range is a mechanical function, not electrical and not related to the CDL activation other than the 4LOW sensor switch.
If you search the forum there may be one hundred threads with your specific issue.

Yes, I'm aware of that. Was stating that it does function. And I've searched the threads on this topic.
Thanks

 

[Woody94]

I’m thinking the light in your dash is out.

Doing figure eights is for the axle locks.
Should not be necessary for the CDL same with putting it up on jack stands.

The diff lock light comes on the dash if I jump the plug to the sensor. Other than that it won't come on manually putting it in 4L or pushing the CDL button

 

[Broski]

The diff lock light comes on the dash if I jump the plug to the sensor. Other than that it won't come on manually putting it in 4L or pushing the CDL button

View attachment 3757652

View attachment 3757653

Well in that case everything from the sensor plug to the light in the dash is working. If you replaced the sensor then maybe you got a bad one.
The next thing I would do is pull the new sensor and check it.