[Shark Bait]

Just put a cap on my 2004 2500HD with the heavy towing package and 5th wheel wiring. No problem wiring in the high mounted cap stop light into the brake light circuit but I want to wire the cap interior light to the same circuit that the bed (cargo) light is wired to.


Where is the easiest place to tap into this circuit? What is the color of the wire that powers this light? I need to run the power wire down the drivers side frame rail and tie into the cap wiring in the left (drivers) tail light area.


I can always trace the cargo light circuit down but thought if one of you guys (gals) have done it it would save me a lot of time.

 

[GMCSID]

That is a ground controlled circuit. You would need to tap the ground wire of your cap lights into connector C1 terminal A2 of the I/P relay block located under the I/P to the left of the steering column, by your left foot. It is a gray connector.



<TABLE width="100%" border=1><A name=tab30-1243954><A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1243954&pubid=437&cellId=62019#tab30-1243954" target="_blank">
<H4>Relay Block - I/P C1</H4></A>
<T>
<TR>
<TH vAlign=center align=middle colSpan=4>

</TH></TR>
<TR>
<TH vAlign=center align=middle colSpan=2>


Connector Part Information</TH>
<TH vAlign=center align=left colSpan=2>
<UL =BULLET>
<LI>12193905
<LI>68-Way F Metri-Pack 280 Series Flexlock (GRY) </LI>[/list]</TH></TR>
<TR>
<TH vAlign=bottom align=middle>


Pin</TH>
<TH vAlign=bottom align=middle>


Wire Color</TH>
<TH vAlign=bottom align=middle>


Circuit No.</TH>
<TH vAlign=bottom align=middle>


Function</TH></TR>
<TR>
<TD vAlign=center align=middle rowSpan=2>


A1</TD>
<TD vAlign=center align=middle>


LT GRN </TD>
<TD vAlign=center align=middle>


24</TD>
<TD vAlign=center align=left>


Backup Lamp Supply Voltage - BCM</TD></TR>
<TR>
<TD vAlign=center align=middle>


LT GRN </TD>
<TD vAlign=center align=middle>


24</TD>
<TD vAlign=center>


Backup Lamp Supply Voltage - Junction Block - Rear</TD></TR>
<TR>
<TD vAlign=center align=middle rowSpan=2>


A2</TD>
<TD vAlign=center align=middle>


DK BLU/WHT</TD>
<TD vAlign=center align=middle>


149</TD>
<TD vAlign=center>


Cargo Lamp Low Control - Cargo Switch</TD></TR>
<TR>
<TD vAlign=center align=middle>


DK BLU/WHT</TD>
<TD vAlign=center align=middle>


149</TD>
<TD vAlign=center>


Cargo Lamp Low Control - BCM</TD></TR></T></TABLE>

 

[Shark Bait]

GMCSID Thanks. I never thought about a ground controlled circuit. With that in mind where would you recommend I pull the positive from? Have not started to dig into the wiring yet so I am not sure what I may be up against.

 

[GMCSID]

In that same connector, B6, B7 and B11 are battery positive voltage.