Body Control Module (BCM) Testing and Repair Service

The body control module, or BCM, is a critical controller of non-engine-related vehicle electronics, and when it’s in need of a repair, it’ll cause a huge range of issues. Thankfully though, if you’ve got a BCM fault you’re in the right place – we’re the experts at testing and rebuilding body control modules in just 2-3 working days. Fill out our short test form to get started.

You can find popular body control modules we offer our comprehensive test and rebuild service for above and below. Don’t panic if you can’t find the BCM you need repairing, browse our product catalogue for our full range.

Signs your BCM is faulty
This intricate module is responsible for controlling various circuits to ensure certain electrical actuators around the vehicle receive enough power to carry out their function at the right time. 

Here are just some functions the BCM is typically (but not always) responsible for controlling the supply of power for:

• Interior/exterior lighting (including turn signals)
• Electric windows
• Central locking
• Heating/air conditioning
• Windscreen wipers
• Power mirrors
• Sunroof operation
• Heated seats

In addition to losing one or more of the features listed above, when your BCM is defective and needs repairing, it’ll typically stop communicating diagnostically. This will lead you to uncover a communication-related fault code like A3C1 or A3B4 – if this happens, send the BCM off for testing. 

In other cases, a body control module malfunction can prevent the vehicle from starting at all. This happens for a number of reasons and it depends on a module by module basis. For example some BCMs play a role in verifying the car key’s transponder chip, so when defective, it can’t run the necessary security checks to authorise engine start up. In other cases, the BCM is responsible for ignition circuit switching or controlling the starter motor, inevitably this functionality is lost when the BCM has failed internally. 

So if you’ve experienced any of the aforementioned symptoms, there’s a chance your BCM is in need of a repair. However, there are a few more steps to carry out before sending your BCM off for professional testing.

Body control module repair tips
As you know, a body control module fault can materialise in a huge amount of ways and it’s tricky to distinguish a BCM issue from a wiring or fuse-related fault. 

The first thing you need to remember is that a BCM can’t function properly without power or ground. So your first step should always be to verify these connections with a multimeter, but also to ensure its connector is free of any damage or corrosion too.

Likewise check all relevant fuses, if the headlight fuse has blown then no current will reach the bulb until it’s been replaced. You’ll also want to make sure the battery is healthy and outputting around 12.6V before condemning your BCM and sending it off for testing. 

Can a body control module be repaired? 
Depending on the extent of the damage your unit has suffered, in many cases a faulty BCM can be repaired to restore full functionality. Commonly these units suffer from internal failures which can normally be rectified by automotive remanufacturing specialists.

To better understand the health of your BCM, send it to us for comprehensive testing. Thanks to state-of-the-art infrastructure and the very latest testing rigs, we’ll tell you conclusively whether a rebuild of your body control module is viable. Just fill out our test form to begin. 

Body control module: repair or replace?
Having narrowed down their symptoms to a malfunctioning BCM, many affected owners are advised to replace their unit with brand new. However, as we’ve mentioned, these modules are frequently caused to fail due to defects they left the factory with. This means replacement units are vulnerable to the very same issues too. Therefore, sourcing a replacement BCM will simply set you back more time and money than sending it to a repair service, and you’ll remain vulnerable to malfunction.

Instead, we propose having your body control module professionally tested and rebuilt by our team of technicians.