U0140 - LOST COMMUNICATION WITH BODY CONTROL MODULE

The BCM (Body Control Module) is an electronic control module that monitors the electrical system. It also manages some functions such as tire pressure monitor, vehicle alarm, remote keyless entry, mirror heater, door locks, among others. The BCM also receives signals from the seat belt switch, ignition switch, cruise control switch, battery discharge protection, and other switches.

When the U0140 OBDII fault code is set, it is because the BCM is not receiving or sending a signal. This module has not been able to establish communication with the ECM via the CAN bus.

• Check Engine light is on.
• The vehicle does not start.
• Certain BCM functions are not available.
• The engine exhibits noticeable failures at high speeds.
• Acceleration is unstable.
• The vehicle constantly blows fuses.

Reasons for setting diagnostic code U0140 OBD2 are:

• The Body Control Module or CAN bus wiring or connectors may have damage causing a short.
• A control switch, sensor, or actuator monitored by the BCM may be defective.
• If the BCM received a strong impact, it could be in bad condition.

To solve the DTC U0140 OBDII code, take into account this:

• Before starting the diagnosis, check the TSBs available for your vehicle.
• Locate the BCM and verify that the wiring, connectors, and fuses are in good condition. If you find deficiencies such as worn wiring, corroded connectors, or blown fuses, make repairs or changes as necessary.
• Check the power supply at each terminal. If one of these does not receive the necessary power, check the wiring. But if each terminal has the proper power supply, the problem is in the module. In this case, go to a specialized service center.