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

Left Heated Seat


Object Number: 755943  Size: FS
Master Electrical Component List
Heated Seats Description and Operation
Right Heated Seat
B+ Bus Bar
HTD SEAT, ATC, HVAC and A/C Fuses
S313 and S419
G420, G450 and S427 - Utility and Crew Cab
Ign ACC, RUN and RAP Bus Bar
HVAC and CRUISE Fuses
HVAC and CRUISE Fuses
Figure 2:

Right Heated Seat


Object Number: 755944  Size: FS
Master Electrical Component List
Heated Seats Description and Operation
Left Heated Seat
B+ Bus Bar
HTD SEAT, ATC, HVAC and A/C Fuses
S320 and S420
G420, G450 and S427 - Utility and Crew Cab
Ign ACC, RUN and RAP Bus Bar
HVAC and CRUISE Fuses
HVAC and CRUISE Fuses