Brake switch cold side wire

Does anyone know which color wire is the cold side? Wired up everything for a trailer brake controller tonight minus splicing into the cold side of the brake switch.

There isn’t much room to get a tester up there so curious if anybody has a diagram or knows which wire it is.

Jeep is a 2001.


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There should be a blue trailer brake wire coiled up or buried behind the left side kick panel.

The brake output(brake lights) should be "white/tan".