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Cab marker lighting wiring install help needed

Sour_Squirrel

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Sour_Squirrel Enthusiast

Sour_Squirrel

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I’m in the process of installing cab marker lights on my 2017 GMC 1500 Sierra SLE. 

From my research there’s a connector that’s located in the passenger side fuse panel where the cab marker harness connects to for power and ground.  

I believe it’s pin 1 for ground and pin 3 for power.   I connected a voltmeter to those pins and am not measuring any voltage when my parking lights are turned on.

Can someone tell me if there should be power at these pins even though the 1500 trucks never came with cab marker lights.   From some articles I read it should be plug and play.  

Is there a fuse for this circuit?

How can I find out where the voltage to these pins come from?

pgamboa Senior Enthusiast

pgamboa

Posted
Posted
I’m in the process of installing cab marker lights on my 2017 GMC 1500 Sierra SLE. 
From my research there’s a connector that’s located in the passenger side fuse panel where the cab marker harness connects to for power and ground.  
I believe it’s pin 1 for ground and pin 3 for power.   I connected a voltmeter to those pins and am not measuring any voltage when my parking lights are turned on.
Can someone tell me if there should be power at these pins even though the 1500 trucks never came with cab marker lights.   From some articles I read it should be plug and play.  
Is there a fuse for this circuit?
How can I find out where the voltage to these pins come from?

In my quest for finding an alternate park Lamp circuit inside the cabin (for the tow mirror cargo Lamp tie in), I explored this passenger side fuse panel. There is a park Lamp landing BUT... the back side of this landing is not present. The back side splices off the run that goes under the hood and into the X50A Fuse Block. That’s most like the reason you have no voltage present.


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Sour_Squirrel Enthusiast

Sour_Squirrel

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That’s what I was afraid of and was hoping not to hear.  

As mentioned I was reading how someone installed the cab marker lights in his truck by just taping into this circuit in the fuse panel.  

Msybe the pin has voltage only in the 2500/3500 trucks( ??). 

Jaychevy81 Enthusiast

Jaychevy81

Posted
Posted

When I installed mine on my 15 I had the same issue no power to pin 3. I had read some just put a missing fuse in but I had no pins. Something with the plow prep package that you could just use that plug but I didn’t have it. Easiest way I did it was the passengers floor kick panel the harness that runs the mirror harness I found the park light wire and T tapped it wasn’t that bad to do. I sued the upfitters wiring PDF to locate that wire. Hope this helps.


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pgamboa Senior Enthusiast

pgamboa

Posted
Posted

If you have pin 11 in the door jamb, you can tap that if the original use panel location is not hot.


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