Diff Lock Troubleshooting Ideas? (1 Viewer)

[Elfego]

Hi all, I am trying to troubleshoot the diff lock light not turning on in my dash.

When I put the T-Case in 4L, I hear it clicking but not motor noise.
No Center Diff Lock light and no ABS light on.

Today I got into the dash and I connected the Center Diff connection to the Hazard light switch to see if that would work.
When I turn it on, I am able to hear the little motor engaging, but the center diff lock light and the ABS light do not come on.

I can confirm that the ABS light is functioning as it comes on in the light pre-check when turning the car on.

Could I just have a faulty center diff light in the cluster?

I have not had time, but will try to see if the rear and front lockers engage when I turn them on AFTER I turn on the center diff through the dash switch.
If it does, I will know center is engaging.

Any other ideas of what could be going on? Will try to check the switch on top of the t-case later tonight.

Thanks,

 

[Elfego]

Here’s a quick video of what I’ve tried.

 

[z531519]

Did you try driving it to see if it engages? I know it's not instant (engage and disengaging), but i can't remember if there are any light indications (blinking ) like the diff lockers have for engaging

 

[Elfego]

Did you try driving it to see if it engages? I know it's not instant (engage and disengaging), but i can't remember if there are any light indications (blinking ) like the diff lockers have for engaging

Only front and back a couple feet, but I had the rear diff light flashing at the same time. No luck there.
Should I try a longer drive? 100ft in a straight line?
I don't think it has been used ever so could be a reason why the light does not come up. But it is odd because I hear the motor engaging, but no lights popping up.

 

[z531519]

Only front and back a couple feet, but I had the rear diff light flashing at the same time. No luck there.
Should I try a longer drive? 100ft in a straight line?
I don't think it has been used ever so could be a reason why the light does not come up. But it is odd because I hear the motor engaging, but no lights popping up.

find a gravel spot if you are worried about binding to exercise all those lockers. The actuator motor engages but they will lock only when the teeth line up (or whatever the mechanics in the CDL is). You'll find a lot of results here about doing figure 8s when testing our lockers. But hearing the motor whirr is a good sign!

 

[Elfego]

find a gravel spot if you are worried about binding to exercise all those lockers. The actuator motor engages but they will lock only when the teeth line up (or whatever the mechanics in the CDL is). You'll find a lot of results here about doing figure 8s when testing our lockers. But hearing the motor whirr is a good sign!

Will give that a go an will update the thread.

Thanks,

 

[ppc]

No CDL and ABS lights on the dash is most likely the CDL Indicator Sensor on the front of the transfer case is not functioning.
The dash lights need to be functioning before the front and rear lockers will engage otherwise you will only get flashing lights.

 

[Grandlooser]

Not only should you drive more, but make a shallow turn at low speed to get the cogs to line up.

 

[Elfego]

Alright, I was finally able to get the 80 into a gravel road yesterday. Started driving in an 8 figure for about 10 minutes until the center diff lock light FINALLY came on. After it came up I turned the front and rear ones and instantly the lights went solid. I tested them out again later that afternoon and the lights turned on instantly. I can safely say they are working!

 

[Grandlooser]

Just keep using them regularly to keep them freed up. My center was sticky from lack of PO use. I cycled it 30-40 times till it would engage instantly