Help BCM Code B827A After Engine Rebuild

[Abdullah576]

I’m hoping someone has run into this before. I have a 2022 Chevy Suburban 5.3L, and ever since I had the engine rebuilt, I’ve been getting a BCM code B827A – “Body Control Module Requested Malfunction Indicator Lamp Illumination.” This code was never present before the rebuild.


The engine runs fine, but the warning light is now on. From what I understand, B827A isn’t necessarily the root cause—it just means the BCM is requesting the MIL because another module has detected a problem.


Has anyone experienced this after an engine replacement or rebuild?

• Could it be a missed ground strap or loose connector?
• Is there a common harness or sensor that’s easy to overlook during reassembly?
• Did anyone have to perform a relearn or module programming afterward?

I’d appreciate any suggestions or if you’ve fixed this before. Thanks in advance!

 

[2024 White Tahoe]

I’m hoping someone has run into this before. I have a 2022 Chevy Suburban 5.3L, and ever since I had the engine rebuilt, I’ve been getting a BCM code B827A – “Body Control Module Requested Malfunction Indicator Lamp Illumination.” This code was never present before the rebuild.


The engine runs fine, but the warning light is now on. From what I understand, B827A isn’t necessarily the root cause—it just means the BCM is requesting the MIL because another module has detected a problem.


Has anyone experienced this after an engine replacement or rebuild?

• Could it be a missed ground strap or loose connector?
• Is there a common harness or sensor that’s easy to overlook during reassembly?
• Did anyone have to perform a relearn or module programming afterward?

I’d appreciate any suggestions or if you’ve fixed this before. Thanks in advance!

View attachment 489380

Did you return to the business that rebuilt the engine?

 

[fondupot]

Could be something as simple as a bad battery, or a loose connection somewhere.