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

Valve Controls and Brake Switch


Object Number: 866585  Size: FS
Master Electrical Component List
Electronic Component Description
Switch Inputs
Automatic Transmission Schematic Icons
BRAKE, HTR A/C, HVAC I
IGN 0 , TBC IGN 0, TBC ACCY, SEO ACCY, W/S WIPER, RR WIPER
BRAKE, HTR A/C, HVAC I
IGN 0 , TBC IGN 0, TBC ACCY, SEO ACCY, W/S WIPER, RR WIPER
4.8, 5.3, 6.0, and 8.1L Cruise Control Schematics - 2 of 2
4.3L Cruise Control Schematics - 2 of 2
8600 GVW or Less - 2 of 2
Figure 2:

Switch Inputs


Object Number: 866586  Size: FS
Master Electrical Component List
Electronic Component Description
Tow/Haul Switch and PNP Switch Inputs
Valve Controls and Brake Switch
Automatic Transmission Schematic Icons
Figure 3:

Tow/Haul and PNP Switch Inputs


Object Number: 866587  Size: FS
Master Electrical Component List
Electronic Component Description
Vehicle Speed Signal and 4WD Low Signal
Switch Inputs
Automatic Transmission Schematic Icons
G203-3 of 3
SP205 - 2 of 2
G203-1 of 3
G102, G103-Gas
Figure 4:

Vehicle Speed Signal and 4WD Low Signal


Object Number: 866589  Size: FS
Master Electrical Component List
Electronic Component Description
Tow/Haul Switch and PNP Switch Inputs
Automatic Transmission Schematic Icons