When the BCM is malfunctioning, it can cause issues with the components it controls. You may experience problems like power locks or windows not working properly, interior lights flickering or not turning on, issues with the anti-theft system or airbags, and warning lights turning on the instrument cluster.
A faulty BCM will likely need replacement or repair to restore proper functionality and ensure the safe operation of your vehicle. BCM repair or replacement can often be done without needing to replace expensive components like actuators or motors. Technicians can run diagnostics to locate the source of issues in the BCM’s circuitry or software and perform repairs to correct them.
In some cases, water damage or physical impacts can also be responsible for BCM issues. Repairing a BCM is often more cost-effective than replacing an entire module, saving vehicle owners time and money. However, if the BCM cannot be repaired, replacement may be necessary to get your vehicle’s systems functioning properly again.
BCM repair and replacement services should only be performed by certified technicians with the proper knowledge, training, and equipment to do the job correctly and safely. They can properly diagnose problems, perform necessary repairs, and ensure all systems are working as intended to keep you and your vehicle secure on the road.
Common BCM Failure Modes and Symptoms
As with any electronic component, BCMs can experience issues that lead to failure over time. It is important to understand the common symptoms of a failing BCM to determine if replacement or repair is needed.
Loss of Vehicle Functions
If your BCM is malfunctioning, you may lose control of certain vehicle features like power locks, windows, interior lighting, and instrument panel gages. The BCM coordinates all of these systems, so failures often impact multiple areas.
Functions that are controlled by the BCM may work sometimes but not others, or seem to turn on and off randomly. For example, power locks or interior lights that activate intermittently could indicate a BCM problem.
Warning Lights Illuminated
The BCM communicates with your vehicle’s computer systems. When it detects an issue, it can trigger the check engine light or other dashboard warnings to alert the driver. Pay attention to any warning lights that come on, as they can point to an underlying BCM failure.
In some cases, a malfunctioning BCM can prevent your vehicle from starting properly. This is because the BCM controls components needed to start the engine like the ignition switch, starter relay, and fuel pump. If these parts are not activating due to a BCM issue, the engine will not turn over.
A failing BCM can cause an array of problems that impact your vehicle’s functionality, safety, and performance. If you experience any symptoms of BCM failure, it is best to have the module tested by a certified mechanic as soon as possible. They can properly diagnose the issue, perform any necessary repairs or replacement to get your vehicle back on the road.
Options for BCM Repair or Replacement
If your vehicle’s body control module (BCM) is malfunctioning, you have a few options for repair or replacement.
Repair the Existing BCM
The first option is to have the existing BCM repaired by a certified technician. They will diagnose the issue, repair or replace damaged components on the module, then reinstall and reprogram it for your specific vehicle make and model. BCM repair tends to be more affordable than replacement but may only provide a temporary fix if there are irreparable issues with the unit.
Purchase a Remanufactured BCM
You can also purchase a remanufactured, or “reman,” BCM. Remanufactured units are OEM BCMs that have been rebuilt to like-new condition. Technicians disassemble the units, replace or repair all damaged or worn out components, reassemble, and fully test to ensure quality and reliability. Reman BCMs often come with a limited warranty and must be programmed for your vehicle before installation. This option may cost slightly more upfront but can provide an affordable, longer-lasting solution.
Buy a New OEM BCM
Purchasing a brand new original equipment manufacturer (OEM) BCM is typically the most expensive option but will provide a permanent solution. New OEM BCMs are built to the exact specifications of your vehicle make and model. However, the new unit will still need to be properly programmed and coded to your vehicle’s VIN to function correctly. While the most reliable long-term solution, a new OEM BCM may cost significantly more than repair or reman options.
In summary, you have a choice between repairing or replacing your malfunctioning BCM. Discuss the options with a certified technician to determine the most appropriate solution based on the age, make, model of your vehicle, and the severity of issues with your current BCM unit. They can provide an accurate diagnosis and cost estimates for each option to help you make an informed decision.
How to Find a Qualified Shop for BCM Repair
To find a qualified shop for body control module (BCM) repair or replacement, it’s important to do your research. The BCM is an intricate and costly component, so you want a shop with extensive experience servicing them.
Ask for Referrals
Ask for Referrals
Talk to friends or family members who have had BCM work done on their vehicles. Ask them about their experience with the shop, if the issue was properly diagnosed and fixed the first time, and if the cost seemed reasonable. Referrals from trusted sources are one of the best ways to find reputable service.
Check Certifications and Reviews
Make sure any shop you’re considering is certified by the vehicle manufacturer to work on that make of car. Certified shops have the proper training, tools, and software to service the vehicle’s systems correctly. Read online reviews from sources like Yelp or the shop’s Google listing. Look for an overall positive rating and reviews mentioning good experiences with electrical system or computer repairs.
Ask About Experience
Call or visit the shops you’re interested in and ask about their experience with BCM replacement and testing. An ideal shop should have several years of experience diagnosing and repairing BCM issues, with technicians trained to work on your specific vehicle make and model. They should own the proper diagnostic scanners and have access to factory service information for your vehicle.
Get an Estimate
Have the shops you’re considering inspect your vehicle and provide a written estimate for the necessary repairs. Compare the estimates between shops to determine which one seems the most thorough and fairly priced. Be very wary of estimates that seem too good to be true, as cutting corners on BCM service could lead to future problems.
Choosing a qualified, experienced shop to service your vehicle’s BCM is essential for a successful repair or replacement. Do your due diligence by checking certifications, reading reviews, and getting written estimates from multiple shops. While BCM work can be expensive, using a reputable shop will give you peace of mind that the job will be done properly the first time.
What to Expect During the BCM Repair Process
Once you have scheduled your BCM repair service, the repair process will typically involve the following key steps:
The technician will first connect your vehicle to a diagnostic scan tool to pull diagnostic trouble codes from the BCM to determine where the issues lie. They will then perform visual inspections of related systems like lighting, locks, windows, etc. to determine if the problems are directly related to a BCM malfunction or another component in the system.
Removal and replacement
If a BCM replacement is necessary, the technician will disable the battery to deactivate the airbag system before removing components to access the BCM module. The BCM will then be disconnected and removed, with a replacement module installed and secured in place. All components will be reassembled and reconnected.
Programming and coding
The new BCM module will need to be programmed to properly function within your vehicle’s electrical system. The technician will connect to your vehicle’s onboard diagnostics port to initialize the BCM, input vehicle-specific data like the VIN, and download software updates. They will then test all systems connected to the BCM like power locks, interior and exterior lighting, climate control, etc. to ensure full functionality has been restored.
Final road test
Once programming and system tests have been completed, the technician should take your vehicle for a final road test to monitor all BCM-connected systems in real-world driving conditions and ensure there are no remaining issues before releasing the vehicle back to you.
Going through the complete BCM repair process with a certified technician will get your vehicle’s body control module and related systems functioning properly again so you can get back on the road with confidence. Be sure to schedule a follow-up scan within a few days to confirm no new trouble codes have appeared.