Troubleshooting the 4WD Acutator on a 94 Suburban

[Tinker]

My hubs don't lock anymore and I suspect the actuator. But a couple of questions before I buy another.

What voltage should I see at the plug when I shift to 4H or 4L? I'm getting 12.x, which seems about right
What resistance should I see on the actuator? If I understand the system, its just a heater coil heating up wax; so I would expect pretty decent resistance, right?
Final question, and the stupid one, the system should work with the ignition in ON even if the engine isn't running, right?

Thanks for your help.

 

[Twisted Steel Performance]

You could go the route of no more worries with this kit... https://4x4posi-lok.com/app_chevy-k.html

 

[ak diesel driver]

you can also upgrade to the newer all electric style as well

 

[Big T]

Upgrade to the newer electro servo actuator and never look back.

 

[MrMarty51]

I`m not sure what year the new motor style actuators came into affect but, I am quite sure that if You get one for about a 1997 year that You would be very safe.
Oh yeah, I dont know what the resistance should be on a new or used actuator heater. I always checked that there was at least 12 volts at the plug then just replaced them, they always seemed to work after that.
I would like to someday get the cable kit for My 2000 K3500.

 

[smokymtn65]

Upgrade to newer electric one, add a switch in brown wire so you can use 4 lo to back trailers if you have the need .

 

[JMJNet]

Here is a write up:

GM TRUCK 4X4 ACTUATOR UPGRADE

Those parts can be bought from ebay cheaper now.
The harness can come from RockAuto, make it has the plunger pin.

There are some Youtube video on how to do it also for some other ideas.

There are a few electrical source possbility, one can come from GRN pin (IIRC) inside the cab under the steering dashboard instead like the one suggested in the above write up.

 

[Tinker]

Upgrade to newer electric one, add a switch in brown wire so you can use 4 lo to back trailers if you have the need .

Thanks for the switch idea. That connected some dots for me. I really hadn't thought of the benefit of direct control over locking the front hubs. Now I understand the appeal of the manual option TSP recommended. Your idea makes sense, too.