Factory Installed Cargo Bed Lights Shorting Out

[edbad]

Crazy problem, maybe someone can offer a suggestion.

 

The factory installed cargo bed lights worked when I got truck and for some reason they stopped working. The cargo light fuse blows.

 

I disconnected the lights from the harness and harness from the connector on the block at the rear of the truck. No short between the two wires in the harness measuring the harness only. Replaced the fuse and with harness disconnected and switch on, the cab cargo light comes on and fuse is OK,

 

If I plug in the harness only at the connector on the block at the rear of the truck and turn the switch on, the fuse blows. Again this is with no lights attached to the harness, only the harness connected to the connector block.

 

Cannot figure why the lights worked before and am seeing a short when the connectors are plugged together now, without lights connected. Is it possible something when bad at the connector that when the two are mated it shorts? Never seen anything like this before. Any suggestions greatly accepted.

[crewl1]

Maybe the issue is in the connector? If you are testing the harness while disconnected it may be ok because of relieving stress that gets placed on the plug when attached?

[edbad]

That's the only thing it could be. Why it works for months then started shorting out, no idea. I would like to remove the connector block mounted on the chassis to see if the problem is between these two connectors, but it looks like a nightmare to do. I need to find the color of the two wires in the large connector harness that feeds the block. I would cut those wires and splice them directly to the cargo light harness and bypass the connectors. Anyone have a wiring diagram for that harness?

[crewl1]

That's the only thing it could be. Why it works for months then started shorting out, no idea. I would like to remove the connector block mounted on the chassis to see if the problem is between these two connectors, but it looks like a nightmare to do. I need to find the color of the two wires in the large connector harness that feeds the block. I would cut those wires and splice them directly to the cargo light harness and bypass the connectors. Anyone have a wiring diagram for that harness?

Go here and download the guide, then look for junction block X63A

 

The last group are the courtesy light plug and I believe they state a red wire for +12 and black for ground but you should research it to be sure.

P293-294

 

https://www.gmupfitter.com/files/media/photo/578/Sierra_Silverado_Electrical_Body_Builders_Manual_Service_Manual_2015_en_US.pdf

 

Connector Part Information Harness Type: OEM Connector: 13581768 Service Connector: Service by Harness - See Part Catalog Description: 8 F Terminal Part Information Terminal Type ID Terminated Lead Diagnostic Test Probe Terminal Removal Tool Service Terminal Tray Core Crimp Insulation Crimp I Not Available Not Available Not Available Not Available Not Available Not Available Not Available

X63A Junction Block - Rear Body X6 Pin Size Color Circuit Function Terminal Type ID Option 1-3 - - - Not Occupied - - 4 0.5 RD 1430 Exterior Courtesy Lamp Supply Voltage I - 5-6 - - - Not Occupied - - 7 0.5 BK 1750 Ground I - 8 - - - Not Occupied - -

Revision 1.2

[chuckl1218]

That's the only thing it could be. Why it works for months then started shorting out, no idea. I would like to remove the connector block mounted on the chassis to see if the problem is between these two connectors, but it looks like a nightmare to do. I need to find the color of the two wires in the large connector harness that feeds the block. I would cut those wires and splice them directly to the cargo light harness and bypass the connectors. Anyone have a wiring diagram for that harness?

Ed, am I missing something? Why would you do anything but take it to the dealer and have them fix it? Obviously something is not straight forward here, but if your truck is still under warranty, why cut it? Have them replace whatever is causing it.