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Great offer. It's just about a necessity to have wiring diagrams for any electrical problems.
 

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2004.5 Chevy 2500HD Crew Cab Duramax LLY
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Thanks for your offer. I am looking for the wiring diagram for a 2004.5 Chevy Silverado 2500 HD Crew Cab Duramax LLY, specifically the power to the OBD2. I have 12 volts at the cig lighter, but only 4 volts at the OBD2.
 

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2004.5 Chevy 2500HD Crew Cab Duramax LLY
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It's under the hood, it comes out as 2 wires.
I searched under the fuse block, and had 12.8 volts on the wire, traced it into the firewall and couldn't find any wear/nicks, now I have 9 volts at pin 16 (still not enough to power my scan tool). I'm thinking it would be easier to splice a wire into the back of the left hand cig lighter and take that over to pin 16 on the OBD2. Do you see any problem with powering it this way? Thanks again for your help.
 

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I know it's an old thread but can you still help get diagrams? Need complete transmission/transfer case diagram and pin out. Or if you can a complete diagram of the truck. I ripped the wires out because the company "mechanic" didnt tie the wires up. It's an 03 3500 HD 4x4 a/t 6.6 lly. Not the original lbz.
 

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thomasjkr


The power to pin 16 on the DLC comes from the same source as the cigar lighter according to the wiring diagram. Do have 12V at the cigar lighter? Have anything plugged into the cigar lighter? Charger? Radar Detector? Gum Wrapper? If so, unplug it until your problem is solved.

#45 CIG LTR 15A Cigar Lighter, Data Link Connector (DLC)

Make sure you have power coming out of this fuse. Pull the fuse and make sure you have good contact.
 

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I know it's an old thread but can you still help get diagrams? Need complete transmission/transfer case diagram and pin out. Or if you can a complete diagram of the truck. I ripped the wires out because the company "mechanic" didnt tie the wires up. It's an 03 3500 HD 4x4 a/t 6.6 lly. Not the original lbz.
Check here for your year and model of truck
GM UPFITTER - Body Builder Manuals
 

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2006 LBZ 400K PowerHustler
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Discussion Starter · #14 · (Edited)
I know it's an old thread but can you still help get diagrams? Need complete transmission/transfer case diagram and pin out. Or if you can a complete diagram of the truck. I ripped the wires out because the company "mechanic" didnt tie the wires up. It's an 03 3500 HD 4x4 a/t 6.6 lly. Not the original lbz.
Hope this helps!

EDIT: PDF files included for transmission to TCM and transfer case, down below.
1088684
1088685
1088686
 

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I just bought ProDemand, if you guys need anything let me know. I have the shop version, so 2001 to 2021 trucks just be specific on what you need.
I am wondering where I can find wiring diagram/ schematic for the fog lights on a 2019 silverado 2500hd duramax. I've put in 4 rigid D2 fog lights and need to re do the wiring.
 

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Hope this helps!

EDIT: PDF files included for transmission to TCM and transfer case, down below.
View attachment 1088684 View attachment 1088685 View attachment 1088686
[/QUOTE yes this helps me a ton I really appreciate it. I just bought a 2003 3500 HD with a mechanic's bed on it pretty good shape. It was my work truck that I talk my boss into selling me. One day at work I went to kick it in 4-wheel drive I didn't realize the transmission wiring harness was hanging loose underneath the truck and well I'm pretty sure you can guess what happened after that but on a good note I didn't get a cheaper than what he's asking originally LOL
 
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