This is one of the most frequent OBD2 trouble codes. Read the full article below to know what it means, how to fix it, and what other codes may show related to it.
U0422 is an OBD-II Code that refers to Invalid Data Received from Body Control Module
A U0422 code is a diagnostic trouble code that occurs when the other control modules on the vehicle are not communicating with each other. In this instance the Controller Area Network bus communications, or simply CAN indicates there's a loss of communication with the BCM (Body Control Module).
To ensure the proper operation of the car's onboard electronics, it maintains and controls the many electrical attachments installed in the vehicle's body. Overall, it manages the electric windows, immobilizer system, center locking system, and several other features.
Common causes for this code include:
- Malfunctioning Body Control Module (BCM)
- BCM harness is open or shorted
- BCM circuit poor electrical connection
The symptoms of a U0422 code are:
- Illuminated Check Engine Light
- Vehicle may not start
- Features that are managed by the BCM may not work, including windows, locks, etc.
To diagnose a U0422 DTC code, a technician would:
- Scan for codes in the ECM and look at the freeze frame data for failure.
- Visually inspect the wiring for damage or poor connections.
- Test the electrical circuits for continuity and resistance.
- Check the ground circuit.
- Replace the BCM as needed.
The following are some of the most common mistakes that a technician may make when diagnosing a U0422 code:
- Not thoroughly inspecting all the wiring and connectors.
- Not checking the ground circuit.
- Replacing the BCM when it is not needed.
How serious is this?
A U0422 code in most cases is not a serious issue and can be fixed by inspecting the wiring and connectors, and replacing the BCM if necessary. However, if there is damage to the wiring or connectors, it could cause a more serious problem down the road. So it's important to properly diagnose and fix the code as soon as possible.
What repairs can fix the code?
The following are solutions that may fix this problem:
- Repair or replace any faulty parts such as wiring, connectors, or control modules
- Check all the grounds on the vehicle
- Resolve any communication issues between modules
- Replace the BCM
A U0422 is related to and may be accompanied by the following codes:
U0100 - Lost Communication With ECM
P1639 - Invalid Data Received From Body Control Module
In conclusion, the U0422 code is a diagnostic trouble code that refers to a problem with the communication between the various control modules on the vehicle. It is not a serious issue, but should be fixed as soon as possible to avoid any further problems. The most common causes of this code are a malfunctioning BCM, a shorted or open BCM harness, or a poor electrical connection to the BCM. The symptoms of this code include the illumination of the Check Engine Light, loss of certain features that are managed by the BCM, and in some cases the vehicle may not start. To diagnose and repair this code, a technician would need to thoroughly inspect all the wiring and connectors for damage or poor connections, check all the grounds on the vehicle, and resolve any communication issues between modules. If necessary, the BCM could be replaced.