Diagnostic Trouble Code
U0145
Lost Communication With Body Control Module "E"
Technical Description U0145
Lost Communication With Body Control Module "E"
What Does This Mean U0145?
This is a generic powertrain code, which means it covers all makes/models, 1996-newer, including but not limited to Ford, Chevrolet, Nissan, GMC, Buick, etc. However, specific troubleshooting steps will vary depending on the vehicle.
The body control module (BCM) is an electronic module that is part of the vehicle's entire electrical system and it controls functions including but not limited to the tire pressure monitor, remote keyless entry, door locks, the anti-theft alarm, heated mirrors, the rear window defroster, front and rear washers and wipers and the horn.
It also receives switch inputs from the seat belts, ignition, the chime telling you the door is ajar, the parking brake, cruise control, the engine oil level, the cruise control and the window washer and wiper. Battery rundown protection, the temperature sensor and the low power mode function may all be affected by a bad BCM, loose connection to the BCM or an open/short in the BCM's harness.
Code U0145 pertains to the BCM "E" or the wiring to the BCM from the engine control module (ECM). The code, depending on the year, make and model of the vehicle, may mean that the BCM is bad, that the BCM is not receiving or sending a signal, the BCM harness has an open or short, or that the BCM is not communicating with the ECM via the controller area network – the CAN communication line.
An example of a Body Control Module (BCM):
The code may be detected when the ECM has not received an emission-related CAN signal from the BCM for at least two seconds. Note: This DTC is basically identical to U0140, U0141, U0142, U0143, and U0144.
The body control module (BCM) is an electronic module that is part of the vehicle's entire electrical system and it controls functions including but not limited to the tire pressure monitor, remote keyless entry, door locks, the anti-theft alarm, heated mirrors, the rear window defroster, front and rear washers and wipers and the horn.
It also receives switch inputs from the seat belts, ignition, the chime telling you the door is ajar, the parking brake, cruise control, the engine oil level, the cruise control and the window washer and wiper. Battery rundown protection, the temperature sensor and the low power mode function may all be affected by a bad BCM, loose connection to the BCM or an open/short in the BCM's harness.
Code U0145 pertains to the BCM "E" or the wiring to the BCM from the engine control module (ECM). The code, depending on the year, make and model of the vehicle, may mean that the BCM is bad, that the BCM is not receiving or sending a signal, the BCM harness has an open or short, or that the BCM is not communicating with the ECM via the controller area network – the CAN communication line.
An example of a Body Control Module (BCM):
The code may be detected when the ECM has not received an emission-related CAN signal from the BCM for at least two seconds. Note: This DTC is basically identical to U0140, U0141, U0142, U0143, and U0144.
Symptoms U0145
1
Misfiring at high speeds
2
Shaking when you increase your speed
3
Poor acceleration
4
The vehicle may not start
5
You may consistently blow fuses
Solutions & Repair Steps U0145
Before you attempt to diagnose the BCM, check the technical service bulletins for the BCM on your vehicle. If a problem is known and covered under warranty, you'll save yourself the diagnostic time. Locate the BCM on your vehicle by using the appropriate repair guide for your vehicle as the BCM may not be in the same place for different models.
You can help determine if the BCM or its wiring is the problem by noting which things are not working on the vehicle such as the door locks, the remote start and other things that the BCM controls. Of course, you should always check the fuses first – check fuses and relays (if applicable) to the non-working functions and for the BCM.
If you believe the BCM or the wiring is bad, the easiest thing to do is to check the connections. Gently wiggle the connector to ensure that it is not loose. If not, remove the connector and check to see that there is no corrosion on both sides of the connector. Check to ensure that none of the individual pins are loose.
If the connector looks fine, then you'll need to check for power at each terminal. Use a diagnostic code reader for body control modules to help you determine which pin or pins have an issue. If any of the terminals are not getting power, then the problem is most likely in the wiring harness. If the terminals are getting power, then the problem is in the BCM itself.
You can help determine if the BCM or its wiring is the problem by noting which things are not working on the vehicle such as the door locks, the remote start and other things that the BCM controls. Of course, you should always check the fuses first – check fuses and relays (if applicable) to the non-working functions and for the BCM.
If you believe the BCM or the wiring is bad, the easiest thing to do is to check the connections. Gently wiggle the connector to ensure that it is not loose. If not, remove the connector and check to see that there is no corrosion on both sides of the connector. Check to ensure that none of the individual pins are loose.
If the connector looks fine, then you'll need to check for power at each terminal. Use a diagnostic code reader for body control modules to help you determine which pin or pins have an issue. If any of the terminals are not getting power, then the problem is most likely in the wiring harness. If the terminals are getting power, then the problem is in the BCM itself.