So here is where Im at. I did my PHH this weekend. While waiting for the cooland to drain and down time, I decided to install my CDL switch that has been sitting on my desk. My 94 came un-locked no switch. I orded my switch used from a junk yard. Everything went into place just fine. Finished the PHH job and took for a test spin.
Ran over to a dirt parking lot, Put her into N, then 4H to N to 4L. No CDL or ABS light on the dash. At this point the 7pin had not been done. Pushed the CDL switch in... no lights again. Tried several times shifting in and out of 4L to 4H. Switch on and off. Tried several figure 8's. I noticed no difference in its turning or driving, leading me to believe the CDL is not engaging. Pulled the battery and reset the ECU by removing the fuses. Put all back together. Same thing. So after a suggestion to go ahead and do the 7pin mod, I tore it back apart, removed the 7pin. Same issue.
I have tested the CDL relay (transmission relay where the 7pin is) and CDL switch on dash using a volt meter/continuity tester.
I have checked the "diff" and "gauge" fuses. Ok.
I have most the CDL articles RE problems on the forums.
I have been going thru these steps on troubleshooting the CDL system:
Troubleshooting the Toyota FJ80 Land Cruiser Center Diff Lock (CDL) | Pacific Northwest Backroad Adventures
I have not been underneath yet to check the 4L switch and actuator.
Anything else I can check?? or Im just missing?
Keep in mind without the CDL switch or 7pin the Center Diff would engage fine in 4L, used just a few weeks ago. Maybe it stopped working before the install and phh job and I havent needed to use it.