A car is incomplete without an OBD2 scanner. This onboard diagnostic scanner is used to find any problem with the vehicle in advance. You can notice the trouble with the code version. Just like that, “U” is mainly used to communicate issues facing users when using the car. And U0140 is especially a lost body control module.
Meaning of the trouble code U0140?
When you notice the U0140 code, you must know the problem related to the communication problem with the body control module with other modules. That means the code reminds it of lost communication with a body control module. But sometimes, when the car faces a problem with the data control module, it shows the same code. This failure is associated with the Powertrain control module, and it detects communication problems with itself and the body control module with the Controller Area Network bus system.
So in easy terms, when the Body control module functions and their system is unable to manage the engine, fuel system, or any operation of breaks with the transmission. The BCM module controls major operations like power seats or wind, door power locks, automatic whimper or rain detection, security system, restraint system like airbags or seat belt tensioners, etc.
So you must know the body control system connected with all types of control systems via the CAN bus system. This module also allows the high-speed serial communication system with the help of other control modules. This module also shares the data and commands in the typical situation of the vehicle. And this all modules are pre-programmed information, that contain all information of the transmitting module. This also shares data with other control modules.
On the other hand, each module receives information periodically from other control modules in a specific network. It verifies that the transmitting and receiving modules are used and perform as expected. And this exchange of information is monitored continually, and PCM detects the break for communication between itself and any part of the system to control the other module. So when the control bus fails to communicate with other modules, you can notice the code U0140.
Location of U0140 sensor:
Mainly the U0140 sensor is located primarily in different places for different cars. But most of the time, you can notice the control module behind or under the dashboard or center of the console. But for some vehicles, you also find this body control module under the front seat. To find the module very quickly, I suggest you go with the TSBs. This bulletin got every detail of your car. And with the help of this manual, you can easily find the module and quickly solve the problem. But sometimes, it’s hard for some cars to find the body module because it is also PCM.
Symptoms of the U0140 trouble code:
You can notice some symptoms when your car faces the U0140 code. Like:
- Malfunction indicator light or MIL “ON,”
- Somebody control function face problems in working time,
- At high speed, it causes misfires,
- When you increase the speed of the car, it shivers,
- Acceleration poor,
- Facing problems when starting,
- Blow fuses all the time.
The reason for the Code U0140:
There are many reasons behind this trouble code U0140. But mainly when the body control module fails to communicate, you can notice the problem. This problem involves other trouble like wiring issues, poor connection in the control module, etc. Be careful because the CAN bus system is connected with almost all circuits, and they are interconnected. When you notice the problem, you must keep in mind that there is also a situation like a melted wiring harness. For that, you also need to examine all over the circuit separately. And this is a tough job because you need to go through thousands of circuits for that. There is also some other problem behind the trouble code. Like:
- Any poor or damaged wiring and/or connectors in the control module of the CAN bus system,
- Defective or broken control module,
- Malfunction in control switches, sensors, locking mechanisms, or actuators in any system of the BCM.
- Fault in PCM. But this is not a very common problem.
- The Body Control Module harness is open or short.
Diagnosis process of the Code U0140:
The diagnosis process is not so complex for the trouble code U0140. Like:
- First, check the wiring of BCM,
- Check the electrical connectors and harness system of the body control module,
- If you don’t find the problem, get help from the technical service bulletin or TSBs because this contains all your car’s details.
Repair the trouble Code of U0140:
After you diagnose the trouble code U0140, it needs to fix the problem as soon as possible. You can check the TSBs or your car’s manual to find the problem quickly for the first step. This manual contains details part of your vehicle. If you find the problem and still have a car warranty, talk to the car company and solve this. It not only saves your money but also saves time.
Fix wiring problem
But if you fail to do this time right that time, then check all the wiring of the BCM. Because sometimes a poorly or broken connected wire is also the reason for this problem. With that, you can notice that some of your car parts are not working correctly, like door lock problems, windshield problems, etc. If you find the wiring problem, then try to repair or replace the wiring system. Sometimes melted or burning plastic of the wiring or spot also create the problem. To solve the problem, use wired bruh to clean the wire and then leave it to dry. I think it will be an excellent solution for your car. And then remove the code from memory. Again program the system and rerun the code.
Check pin connector and CAN bus
If the problem again pops up, the problem is not solved at all. And if there is a loose connection in the wiring, remove the connectors and see any corrosion there. Also, check each pin of the connectors it’s open or not. If the connectors look fine, you need to incept the power situation of the module. That means now you need to check the power terminal of all the CAN bus systems. You need a diagnostic code reader to determine each terminal’s power in the body control module. If any terminal is not getting power, this problem is connected to the wiring harness issue. But if it happens the opposite, like the terminal getting power, then there is a problem with the body control module.
Cost and time to solve the Trouble code U0140:
If you cannot solve the problem by yourself, you need the help of an expert. A professional needs around one hour to solve this type of problem. And this problem is not very costly. It would help about 75 $ to 100$ to repair this problem.
How serious of the Code U0140?
The trouble code of U0140 is related to the car’s body control. It is not serious if you use it for some serious issue. But this problem is associated with the security system. So I won’t suggest you drive the car when you find out the problem. Sometimes you face some difficulties in driving, and sometimes you can’t start the engine. So try to solve the problem as soon as possible.
Kevin Nicholas is an automotive technician who is a genius at software and hardware-related issues. He manually tested more than a hundred OBD scanners and gave his honest opinion on whether the device was worth the money or not. His in-depth OBD review articles help people choose the right product, whether it is a European, American, or Asian vehicle. He completed his Automotive Specialized Training Course at Universal Technical Institute and has more than 15 years of experience in the field.
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