Body Control System: Other Pontiac Sunfire I

Body Control Module (BCM) Programming/RPO Configuration

1. The body control module (BCM) must be programmed with the proper RPO configurations. The BCM stores the information regarding the vehicle options and if the BCM is not properly configured with the correct RPO codes, the BCM will not control all of the features properly. Ensure that the following conditions exist in order to prepare for BCM programming: The battery is fully charged. The ignition switch is in the ON position. The data link connector (DLC) is accessible. All disconnected modules and devices are reconnected before programming.
2. To setup a new BCM, access the SPECIAL FUNCTIONS menu on the scan tool to program the BCM. Select NEW BCM SETUP and follow the instructions on the scan tool.
3. If the BCM fails to accept the program, perform the following steps

1. Inspect all BCM connections.
2. Verify that the scan tool has the latest software version.

Passlock Learn Procedures

Perform the Learn Procedure if any of the following components have been replaced

1. The body control module (BCM)
2. The Passlock sensor Refer to PROGRAMMING THEFT DETERRENT SYSTEM COMPONENTS in Theft Deterrent for the proper procedure.
3. The powertrain control module (PCM) Refer to «SERVICE PROGRAMMING SYSTEM OFF BOARD REMOTE PROCEDURE»(ref-153397-S30256617822003041200000) or «SERVICE PROGRAMMING SYSTEM PASS-THRU PROCEDURE»(ref-153397-S07625288752003041200000) or «SERVICE PROGRAMMING SYSTEM OFF BOARD REMOTE PROCEDURE»(ref-153397-S30256617822003041200000) or «SERVICE PROGRAMMING SYSTEM OFF BOARD PASS-THRU PROCEDURE»(ref-153397-S22728541612003041200000) in Programming for the proper procedure.

1. Turn the ignition OFF for 10 seconds.
2. Connect the scan tool to the data link connector.
3. Turn the ignition ON with the engine OFF.
4. Use the scan tool in order to retrieve history DTCs from all modules.
5. Clear all history DTCs.

The body control system consists of a BCM and it's associated controls. Battery positive voltage is provided to the BCM from CLSTR fuse in the Fuse Block-left I/P. The module ground is wired to ground G201. The BCM is wired to the Class 2 serial data communication bus as well as discreet input and output terminals to control the functions of the vehicles body.

Serial Data Power Mode

On vehicles that have several control modules connected by serial data circuits, one module is the Power Mode Master, PMM. On this vehicle the PMM is the BCM. The PMM receives 2 signals from the ignition switch.

To determine the correct power mode the PMM uses the following circuits

1. Accessory voltage
2. Ignition 1 voltage

Serial Data Messages

The modules that depend exclusively on serial data messages for power modes stay in the state dictated by the last valid PMM message until they can check for the engine run flag status on the serial data circuits. If the PMM fails, the modules monitor the serial data circuit for the engine run flag serial data. If the engine run flag serial data is True, indicating that the engine is running, the modules fail-safe to RUN. In this state the modules and their subsystems can support all operator requirements. If the engine run flag serial data is False, indicating that the engine is not running, the modules fail-safe to OFF-AWAKE. In this state the modules are constantly checking for a change status message on the serial data circuits and can respond to both local inputs and serial data inputs from other modules on the vehicle.

Discrete Ignition Signals

Those modules that have discrete ignition signal inputs also remain in the state dictated by the last valid PMM message received on the serial data circuits. They then check the state of their discrete ignition input to determine the current valid state. If the discrete ignition input is active, battery positive voltage, the modules will fail-safe to the RUN power mode. If the discrete ignition input is not active, open or 0 voltage, the modules will fail-safe to OFF-AWAKE.

In this state the modules are constantly checking for a change status message on the serial data circuits and can respond to both local inputs and serial data inputs from other modules on the vehicle.

BCM Wake-up/Sleep States

The BCM is able to control or perform all of the BCM functions in the wake-up state. The BCM enters the sleep state when active control or monitoring of system functions has stopped, and the BCM has become idle again. The BCM must detect certain wake-up inputs before entering the wake-up state. The BCM monitors for these inputs during the sleep state, where the BCM is able to detect switch transitions that cause the BCM to wake-up when activated or deactivated. Multiple switch inputs are needed in order to sense both the insertion of the ignition key and the power mode requested. This would allow the BCM to enter a sleep state when the key is IN or OUT of the ignition.

The BCM will enter a wake-up state if any of the following wake-up inputs are detected

1. Activity on the serial data line.
2. Detection of a battery disconnect and reconnect condition.
3. Headlamps are on.
4. Ignition is turned ON.
5. Key-in-ignition switch.
6. Parklamps are on.

The BCM will enter a sleep state when all of the following conditions exist

1. Ignition switch is OFF.
2. No activity exists on the serial data line.
3. No outputs are commanded.
4. No delay timers are actively counting.
5. No wake-up inputs are present.

If all these conditions are met the BCM will enter a low power or sleep condition. This condition indicates that the BCM, which is the PMM of the vehicle, has sent an OFF-ASLEEP message to the other systems on the serial data line.

Body Control Module

The various BCM input and output circuits are described in the corresponding functional areas indicated on the BCM electrical schematics. The Body Control Module functions include the following.

1. Retained Accessory Power, RAP, Audio System only. Refer to RETAINED ACCESSORY POWER (RAP) DESCRIPTION AND OPERATION
2. A/C compressor request. Refer to Air Temperature Description and Operation
3. Remote Function Control. Refer to KEYLESS ENTRY SYSTEM DESCRIPTION AND OPERATION
4. A/C cooling Fan. Refer to Air Delivery Description and Operation
5. Exterior and interior lighting control, Refer to EXTERIOR LIGHTING SYSTEMS DESCRIPTION AND OPERATION Daytime running lights (DRL) Automatic lighting control Fog lamps
6. Interior lighting. Refer to INTERIOR LIGHTING SYSTEMS DESCRIPTION AND OPERATION
7. Battery rundown protection (Inadvertent Power). Refer to INTERIOR LIGHTING SYSTEMS DESCRIPTION AND OPERATION
8. Chimes Refer to AUDIBLE WARNINGS DESCRIPTION AND OPERATION Key In Ignition Head Lamps On Seat Belt Not Fastened Turn Signal On Park Brake Warning Door Ajar Warning Check gauges
9. Gauge control. Refer to INSTRUMENT PANEL CLUSTER (IPC) DESCRIPTION AND OPERATION
10. Instrument cluster indicator control. Refer to INSTRUMENT PANEL CLUSTER (IPC) DESCRIPTION AND OPERATION
11. Theft deterrent. Refer to THEFT SYSTEMS DESCRIPTION AND OPERATION
12. Engine coolant level sensing. Refer to «COOLING SYSTEM DESCRIPTION AND OPERATION»(ref-174538-S13401621072005040600000)
13. Key-in-ignition sensing. Refer to AUDIBLE WARNINGS DESCRIPTION AND OPERATION
14. Brake fluid level sensing. Refer to «BRAKE WARNING SYSTEM DESCRIPTION AND OPERATION»(ref-164180-S35795574542005092100000)
15. Parking brake state sensing. Refer to «BRAKE WARNING SYSTEM DESCRIPTION AND OPERATION»(ref-164180-S35795574542005092100000)
16. Rear compartment interface. Refer to POWER DOOR LOCKS DESCRIPTION AND OPERATION
17. Horn interface. Refer to HORNS SYSTEM DESCRIPTION AND OPERATION
18. Door lock interface. Refer to POWER DOOR LOCKS DESCRIPTION AND OPERATION
19. Bulb Check. Refer to INSTRUMENT PANEL CLUSTER (IPC) DESCRIPTION AND OPERATION
20. ETS -Pontiac Only. Refer to ABS DESCRIPTION AND OPERATION
21. A/T Shift lock control. Refer to AUTOMATIC TRANSMISSION SHIFT LOCK CONTROL DESCRIPTION AND OPERATION