Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Body Control Module: Messaging
The BCM uses the following messages received from other electronic modules over the PCI data bus:
- Accessory Delay Control (DDM/PDM)
- Battery Temperature (PCM)
- Chime Request (EMIC, EVIC, SKIM)
- Cylinder Lock Switch Status (DDM)
- Door Ajar Status/Front Doors (DDM/PDM)
- Door Lock Status (DDM/PDM)
- Engine Model (PCM)
- Engine RPM (PCM)
- Engine Temperature (PCM)
- English/Metric Default (EMIC)
- Fuel Tank Level (PCM)
- Fuel Used/Injector Pulses (PCM)
- Panic Control (PDM)
- Programmable Features Preferences/Audible & Optical Chirps/Headlamp Delay (EVIC)
- RKE Status (PDM)
- Vehicle Identification Number (PCM)
- Vehicle Speed (PCM)
The BCM provides the following messages to other electronic modules over the PCI data bus:
- A/C Switch Status (PCM)
- Ambient Temperature Data (AZC/EVIC/PCM)
- Average/Instantaneous Fuel Economy (EVIC)
- Country Code (EMIC)
- Courtesy Lamp Status (DDM/PDM)
- Distance To Empty (EVIC)
- Elapsed Ignition On Timer (EVIC)
- English/Metric Status (EMIC)
- Front & Rear Door Ajar Status (EVIC)
- Front & Rear Fog Lamp Status (EMIC)
- Heated Seat Switch Status (HSM/MHSM)
- High Beam Status (EMIC)
- Ignition Off Timer (EVIC)
- Ignition Switch Position (DDM/PDM)
- Key-In Ignition Status (DDM/PDM)
- Low Beam Status (EMIC)
- Panel Lamp Status (AZC/EMIC/Radio)
- Rear Window Defogger Relay Status (DDM/PDM)
- Remote Radio Switch Status (Radio)
- Seatbelt Status (EMIC/MHSM/MSM)
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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