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Discussion Starter · #1 · (Edited)
4wd engages, H and L, no neutral, front axle engages, shift motor new, switch seems to be good (maybe) but keeps blinking, "service 4wd" indicator comes on, shifts erratic in 4L.
What am I missing? Any thoughts?
Thanks
 

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If it's not pump rub or actuator it's probably the dash switch. Pretty common for them to go out. Easy peezy to replace
 
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Had to replace the switch on my 03. Same symptoms, everything else checked ok
 

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Could be switch in dash. Easy to trouble shoot as each switch position has a distinct resistance value. My problem ended up being the encoder in the transfer case. Also easy to trouble shoot with a power probe.
 

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Then it could be the wiring harness...
I have had issues with bad grounds between the engine, transmission and body causing all sorts of issues. There are a couple of common grounds one I think just below the drivers door on the frame. You could check voltages and resistances on the circuit or just try and clean the grounds and see what happens.
 

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I have had issues with bad grounds between the engine, transmission and body causing all sorts of issues. There are a couple of common grounds one I think just below the drivers door on the frame. You could check voltages and resistances on the circuit or just try and clean the grounds and see what happens.
What truck do you have?
 

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What truck do you have?
05. I had the exact same symptom a while back and traced it to bad grounds. They looked ok, but were corroded and needed cleaning. As these are separate frame vehicles you need low resistance reliable grounds between the body and frame for things to work properly. I have also had issues with the connections to the transfer case motor as well for the same basic reason.
 
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