2014 Chevrolet Silverado 1500 and GMC Sierra 1500; 2015 Chevrolet Silverado and GMC Sierra
When installing an aftermarket bed cap or topper on a 2014 Silverado 1500 or Sierra 1500, or a 2015 Silverado or Sierra, the wiring provisions for the Centre High Mounted Stop Lamp (CHMSL) are provided at the Rear Body Junction Block (X63A) connector X6, terminal 1. Follow the installation guidelines based on the vehicle configuration.
Trucks with the Under Rail Bed Lighting Option
Trucks equipped with the under rail bed lighting option will already have an X6 connector at the Rear Body Junction Block X63A. Obtain an appropriate length of 14-gauge wire to run from the Rear Body Junction Block up to the CHMSL wiring for the cap or topper. Create a terminated lead using the appropriate terminal and wire seal and connect it to one end of the wire.
Disconnect the X6 connector at the Rear Body Junction Block and remove the rubber cavity plug in terminal position 1 and discard. Install the terminated lead into the X6 connector, terminal 1. Run the wire up to the CHMSL for the cap or topper and connect. The ground for the cap or topper CHMSL will need to be made to an appropriate ground.
Truck without the Under Rail Bed Lighting Option
Trucks not equipped with the under rail bed lighting option will have a dummy connector at the X6 position of the Rear Body Junction Block. The X6 connector body is not available separately, but can be obtained by ordering the under rail bed lighting harness. The harness includes terminals/wiring in positions 4 and 7. Remove the wiring from terminal 4 and discard. Move the rubber cavity plug from terminal position 1 into terminal position 4.
Obtain an appropriate length of 14-gauge wire to run from the Rear Body Junction Block up to the CHMSL wiring for the cap or topper. Create a terminated lead using the appropriate terminal and wire seal and connect it to one end of the wire. Install the terminated lead into the X6 connector, terminal 1. Terminal 7 is a ground circuit used for the under rail bed lighting and it can be used to ground the CHMSL for the cap or topper, if desired. If terminal 7 is not used, remove the terminal and install a rubber cavity plug or cut off the additional wiring, leaving a couple inches of wire, and seal the end of the wire.
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