GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2003 🢒 Montana - 4WD 🢒 Body and Accessories 🢒 Body Control System 🢒 Body Control System Schematics
Figure 1:

Ignition Input, Door Locks, and Exterior Lamps Output
Object Number: 685531 Size: FS
Master Electrical Component List
Body Control System Description and Operation
Interior Lights On Request and Horn Control
BATT Main 1 and Fuse Block - I/P Fuses
IGN Main 1, SDM, T/SIG, CRUISE and PCM PASS KEY/CLUSTER Fuses
IGN Main 2, BCM PRGRM, RR WPR/WSHR, MALL/CLUSTER and FRT/WPR/WSHR Fuses
IGN Main 2, BCM PRGRM, RR WPR/WSHR, MALL/CLUSTER and FRT/WPR/WSHR Fuses
IGN Main 1, SDM, T/SIG, CRUISE and PCM PASS KEY/CLUSTER Fuses
IGN Main 2, BCM PRGRM, RR WPR/WSHR, MALL/CLUSTER and FRT/WPR/WSHR Fuses
Content Theft Deterrent (CTD) System
Door Lock Actuators
G200, Page 1 of 3
BCM, Instrument Panel Cluster (IPC) and Grounds
Content Theft Deterrent (CTD) System
Seat Belts
Figure 2:

Interior Lights On Request and Horn Control
Object Number: 685536 Size: FS
Master Electrical Component List
Body Control System Description and Operation
Ignition Input. Door Locks and Exterior Lamps Output
Power, Ground, Class 2 Data Line and Gages
Rear Object Sensor Control Module, Power and Ground
Door Lock Switches
BCM, Headlamp, and I/P Lamp DImmer Switch
Keyless Entry
Horns
Engine Data Sensors - MAF and VSS
Retained Accessory Power (RAP)
BCM, Power and Ground
Park Brake Indocator Switch and DRL Ambient Light Sensor
Door Lock Switches
Key Cylinder Switches
Door Locks, Sliding Door Jamb Switches and Liftgate Door Lock
Tail Lamps, Side Markers and Park/Turn Lamps
BCM, Headlamp, and I/P Lamp DImmer Switch