98 K1500 NP243 4hi and 4 low lights illuminated and wont shift

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I am looking for some input on a place to start. My 1998 K1500 had a CEL Code C0472 and I noticed that my 4 wheel drive is now not working. When I try to shift to 4hi or 4 low both the hi and low lights illuminate and stay that way until I turn off the truck. I have read about a possible actuator but I wanted to reach out for some help before I just start part swapping.

 

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After some additional research I believe the code and the 4 wheel drive issue are not related. I found that none of the 4 wheel drive lights on the switch are illuminated when the truck is on. When I press the 4hi or low button in drive nothing happens. When I shift to neutral and try 4hi both 4 low and 4 hi lights illuminate and stay that way until the truck is turned off. If I put the truck into neutural it does shift to 4 low with a clunk. I do hear a relay clicking when under the dash when I try to shift 4 wheel drive modes. I can feel both the front diff and transfer case actuators doing something when buttons are pressed. Any help is appreciated. I have replace the font diff actuator and the 4 wheel drive switch without correcting the issue.

 

[sbump]

After some additional research I believe the code and the 4 wheel drive issue are not related. I found that none of the 4 wheel drive lights on the switch are illuminated when the truck is on. When I press the 4hi or low button in drive nothing happens. When I shift to neutral and try 4hi both 4 low and 4 hi lights illuminate and stay that way until the truck is turned off. If I put the truck into neutural it does shift to 4 low with a clunk. I do hear a relay clicking when under the dash when I try to shift 4 wheel drive modes. I can feel both the front diff and transfer case actuators doing something when buttons are pressed. Any help is appreciated. I have replace the font diff actuator and the 4 wheel drive switch without correcting the issue.

Just to follow up on my findings. I did Voltage and ohm checks on the encoder motor plug and had some strange readings. Tracing the wires back found where Mice had been chewing on the wires between the back of the engine and firewall.