PAC SWI-PS - Manual (Page 6)

Testing the SWI-PS
Note: For Sony head units, please refer to the note below.
Test each Heater function of the steering wheel controls. The
TEMP and FAN should work properly. When testing the audio
controls, the left LED on the SWI-PS will flash indicating it is
sending a command. If any function does not work, repeat the
programming instructions (starting from Step 11) or refer to
Troubleshooting Guide.
VOL TEMP
Sony Head Units only!: If the Volume and Track/
Seek settings are reversed, you need to program the head
unit to reverse the input. Please refer to the radio's Owners
Manual to change this feature for the wired remote.