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Discussion Starter · #1 ·
Built trans built transfer case (was working) had the 5.7 completely rebuilt and upgraded for towing. Now no 4WD. No power to the transfer case actuator motor. Snapon scanner says no communication to the transfer case.

Fuse 2 and 24 on the fuse block are ok. It was working prior to pulling the motor and going a rebuild. Does this model have a PCM? Or am I missing something somewhere? else.
 

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If the transfer case has a shift motor, it has a Transfer Case Control Module.
Power and instructions go through the TCCM.
Sorry, I don't know where it would be on a '99
 

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Well, doubtful if pulling the engine would blow the TCCM, I suspect it's been left disconnected, or the wiring damaged.
 

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My guess too, probably just ready to crap and it let loose. I am ordering one off Amazon,
Did you read my post?

I suggested you might want to look for damaged wiring, or a connector left disconnected.
 

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Discussion Starter · #7 ·
OK back again. FUSE is popping on #2. On the fuse box, to the left of the dash, top row, #2 pops, SOOOO somewhere I have a pinched or frayed line. The TC was working prior to pulling the motor and rebuilding. I dont know if there are any wires running under the hood, The buttons on the dash lead to the transfer case module (which BTW is above the parking brake on the left side below the dash).

Underside is a mess of wires in and around the transfer case and actuator. Any ideas???
 

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May I ask who pulled and installed the transmission/transfer case? To me it looks like a job done haphazardly to pinch a wire during the install.

Tough to work under the truck.
You can do a tug test on the harness and see if it is free or it was pinched. You shd feel it if it's pinched.

If pinched, you can support and unbolt the transmission cross member and drop it a little until the fuse do not blow anymore.

You can also unplug the transfer case module connectors and perform a resistance test or use a test light with clamp on positive and start probing power and ground pins to look for a dead short.
 

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Discussion Starter · #9 ·
Shop that I used and have used over the past 20 years. THe old 5.7 was beat. So it was pulled and everything was upgraded from an RV cam to top end to heads to .40 over. Headers installed and cats cut off. Its a beast. The secondary air pump was removed.

I got it back and the switches show red light, 2WD and 4L lit up. I first thought the actuator motor had died. NOPE. Snapon scanner cannot communicate with the transfer case. So we did a control module. NOPE. If there is wires leading from the under hood fuse box that I can trace out, I will. So far I cannot find anything messed up. I put a 10mp fuse in #2 it popped
 
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