Body Control Modules: Other GMC Yukon Denali

AMBIENT LIGHT SENSOR

The ambient light sensor has 2 states: light and dark. When headlight switch is in AUTO position while in the light state, the radio, PRNDL display and passenger air bag switch will stay fully bright. If headlight switch is in PARK LAMP or HEADLAMP position while in the light state, the radio, PRNDL display and passenger air bag switch will dim with dimming control. If headlight switch is in AUTO, PARK LAMP or HEADLAMP position while in dark state, the radio, PRNDL display and 4-wheel drive switch will dim with dimming control.

ASLEEP & AWAKE FUNCTIONS

After the ignition switch is turned off and 20 minutes elapse without any wake up signals, the BCM enters an asleep state and goes into the low power mode. Wake up signals turn BCM on to begin controlling and/or monitoring of certain functions. BCM wake-up inputs are as follows

1. Door ajar switches.
2. Door handle switches.
3. Dome light.
4. Parking Lights.
5. Power door lock switches.
6. Interior light request active.
7. Ignition key put into ignition switch.
8. Ignition key removed from ignition switch.
9. Ignition turned on.
10. Key in door lock switch.
11. Remote Function Actuator (RFA) request to BCM.
12. Any class 2 communication requiring BCM interaction.

AUDIBLE WARNINGS (CHIME)

When the BCM determines a driver warning chime is needed, BCM will sound the chime when applicable.

BATTERY RUNDOWN PROTECTION

BCM helps to prevent inadvertent battery rundown from situations such as courtesy lights left on. The BCM will turn off courtesy light circuit after ignition has been off for 40 minutes and no light request input has been received.

DAYTIME RUNNING LIGHTS & AUTO HEADLIGHTS

If headlight switch is in AUTO position while ambient light sensor is in light state, Daytime Running Lights (DRL) are on. If parking brake is set, DRL will turn off until parking brake is released. If headlight switch is in PARK LAMP position while in light state, DRL and parking lights will be on. If headlight switch is in HEADLAMP position while in light state, DRL will be off and both the parking lights and the headlights will be on. If headlight switch is in AUTO position while in light state and ambient light sensor changes to dark state, BCM will turn headlights after 15 seconds. When ambient light sensor is in dark state, DRL will be off regardless of headlight switch position. When ambient light sensor changes form dark to light state, headlights will turn off and DRL will turn on after 20 seconds.

FRONT FOG LIGHTS

Front fog lights are controlled by BCM. Parking lights and/or headlights must be on for fog lights to operate. Fog lights will not operate when high beams are on.

RETAINED ACCESSORY POWER

The Retained Accessory Power (RAP) feature allows power windows, sunroof and radio to be operated after ignition is turned from on to off. Power will be turned off when any door is opened or 20 minutes has elapsed.

ILLUMINATED ENTRY

Interior lights will illuminate for 15 seconds when either outside door handle is lifted and released or either door is opened and closed.

PROGRAMMING

Note. Use of Tech 2 scan tool and Techline® terminal is recommended for programming BCM. A generic scan tool may not be capable of performing all necessary programming functions. Refer to scan tool manufacturer's instructions.

BCM PROGRAMMING/REGULAR PRODUCTION OPTION CODES

BCM must be programmed with proper Regular Production Option (RPO) configurations. If BCM is not properly programmed with correct RPO codes, the BCM will not be able to control the features properly. Before programming BCM ensure battery is fully charged, ignition is turned on and Data Link Connector (DLC) is accessible. Follow instructions on scan tool to program BCM. If BCM fails to accept programming or RPO codes, check connections at BCM and ensure scan tool has latest software updates. When BCM is replaced, Passlock™ must also be reprogrammed. See PASSLOCK™ LEARN PROCEDURES.

Passlock™ RELEARN PROCEDURE

Note. A scan tool and Techline® terminal can be used to perform relearn procedure. Refer to scan tool and Techline® terminal manufacturer's instructions. Procedure will take about 10 minutes with use of scan tool and Techline® terminal.

Note. Module reprogramming must be performed before attempting Passlock™ relearn procedure if any of the following components are replaced: Passlock™ sensor, BCM, PCM or VCM.

1. Turn ignition on, then to start (without starting engine), then back to on.
2. Observe SECURITY indicator light on dash for 10 minutes. After 10 minutes, indicator light will transition from on to off.
3. Repeat steps 1 and 2 twice. After successfully completing 3 consecutive cycles of ignition switch, vehicle will learn new component on next ignition cycle, which is from off to start then to on. Engine should start.
4. After performing relearn procedures, use scan tool to clear DTCs.

BODY CONTROL MODULE (BCM)