GM Service Manual Online
For 1990-2009 cars only
Figure 1:

Trailer Lighting Control - Export 1 of 2 and all Domestic


Object Number: 2075722  Size: FS
Figure 2:

Export Trailer Wiring - 2 of 2


Object Number: 2075724  Size: FS
Figure 3:

Trailer Brake Control - Domestic


Object Number: 2075726  Size: FS