How to Determine if the BCM is Faulty?

[MichaelLynn]

BCM stands for Body Control Module in a vehicle. Symptoms of a faulty BCM are as follows: 1. For automatic transmission models: The trunk cannot be opened, the car key cannot be removed, the P gear is locked, the brake lights do not illuminate (high-mounted brake light functions normally), the windshield washer does not work, and the cigarette lighter does not work. 2. For manual transmission models: The trunk cannot be opened, the width indicator lights do not illuminate, the brake lights do not illuminate (high-mounted brake light functions normally), the windshield washer does not work, and the cigarette lighter does not work. The functions of the BCM are as follows: 1. Power management: It integrates the power supply of electrical devices in the vehicle into the BCM, saving wiring harnesses and facilitating later maintenance. 2. Light control: Prevents the vehicle's wiring harness from burning out due to excessive current. 3. Wiper control: Using the BCM effectively saves wiring harnesses and enhances the functionality of the wipers. 4. Self-diagnosis: Controls vehicle body anti-theft and engine anti-theft, as well as fault mode self-diagnosis control.