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BCM Input/Output Information

The following components provide direct input to the Body Control Module (BCM). Other systems can use this input information in order to carry out certain functions:
BCM Inputs
^ Ambient Light Signal Processing - provides the BCM with the ambient light input information for interior lamp illumination.
^ Column Feedback Switch - provides steering column feedback information to the BCM in order to determine if the steering column was successfully locked or unlocked.
^ Door Ajar Switches - provides door ajar status to the BCM.
^ Electronic Traction/Suspension Control Switch -. provides traction control switch activation input to the BCM in order to turn the TCS status ON or OFF.
^ Fog Lamp Switch, Front - provides fog lamp switch activation input to the BCM in order to turn the front fog lamps ON or OFF.
^ Fog Lamp Switch, Rear - provides fog lamp switch activation input to the BCM in order to turn the rear fog lamps ON or OFF.
^ Hatch Ajar Switch - provides hatch ajar status to the BCM.
^ Hatch Release Switch - provides hatch release switch information to the BCM.
^ Hood Ajar Switch - provides hood ajar status to the BCM.
^ Ignition Switch - provides the BCM with ignition position status.
^ Key In/Out Ignition Switch - allows the BCM to detect when a key is in or out of the ignition.
^ Monitored Loads - monitors electrical loads left ON after the ignition switch is turned OFF.
^ PASS-Key(R) Resistance - determines the resistance of the key for the PASS-Key(R) system.
^ Rear Defogger Switch - provides rear defogger switch activation input to the BCM in order to turn the rear defogger ON or OFF.
^ Turn Signal Monitor, LH/RH - monitors the turn signal status for the DRL.

The BCM directly controls the following outputs. Other systems may request the BCM to control These outputs for certain functions:
BCM Outputs
^ Backup Lamp Relay - provides output control in order to energize the backup lamp relay for UTD and Approach Lighting.
^ Column Lock/Unlock Control - controls the steering column lock/unlock motor position.
^ Console Lamp Dimming Control - controls the console lamp illumination when the headlights or the parklights are ON.
^ Courtesy Lamp Relay - provides output control in order to energize the courtesy lamp relay when an ON request is received.
^ DRL Relay, LH - the energized relay allows the BCM to use the LH front turn signals for DRL, Approach Lighting, and UTD functions.
^ DRL Relay, RH - the energized relay allows the BCM to use the RH front turn signals for DRL, Approach Lighting, and UTD functions.
^ Fog Lamp Relay, Front - provides output control in order to energize the front fog lamp relay when an ON request is received.
^ Fog Lamp Relay, Rear - provides output control in order to energize the rear fog lamp relay with a fog lamp switch ON request, or for Approach Lighting and UTD functions.
^ Horn Relay - allows the BCM to energize the horn relay for UTD and RFA system functions.
^ HVAC Lamp Dimming Control - controls the HVAC lamp illumination when the headlights or the parklights are ON.
^ Monitored Load Relay - provides output control for the load monitor relay, allowing the BCM to shut off certain electrical loads in order to prevent battery rundown.
^ PRNDL Lamp Control - controls the PRNDL lamp illumination when the headlights or the parklights are ON (A/T only).
^ Rear Defogger Relay - provides output control in order to energize the defogger relay with a switch ON request.
^ Theft Deterrent Relay - allows the BCM to energize the theft deterrent relay for UTD.