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help limp mode

3K views 5 replies 2 participants last post by  lddrew 
#1 ·
Hey guys, had my transfer case replaced last week and I had a code come up today and stuck in limp mode. Codes were P0700 trans control system, P0721 output shaft sensor circuit range/performance, P0763 shift solenoid c electrical, P0768 shift solenoid d electrical. I'm assuming the first two were not cleared from the transfer Case swap, but what about the others. Cleared codes this morning, we will see if they come back.
 
#2 ·
how do I troubleshoot and repair the shift solenoid problems
 
#3 ·
so check engine light went on again on the way home. stuck in limp mode and this time wont go into reverse. shift to reverse and the light blinks under the r. clunks hard back into drive. need help asap. anyone?
 
#4 ·
so looked at the nbsu wiring and found that 2 wires were shorted out on the frame. black and yellow i believe. spliced black because it was not continuous and taped up yellow. started up truck and it will hesitate but will go into reverse. back to drive still clunks hard. possible bad nbsu switch? wires shorted fried electronics in the switch or is there something else im not thinking of?
 
#5 ·
took the truck back out for a spin and the check engine light went off and it worked normally. i think the two wires grounding out were causing my problem. for now im calling it fixed.
 
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