Does anyone have this issue?

Wonder if it could be just moisture and salt messing with a sensor.

2015 LML deleted EFI.

I'm getting the service trailer brake system warning on the dash.

It comes on for a second and turns off.

I had nothing hooked up to it during this time.

I have my tail light bar spliced into those wires CORRECTLY, so I don't think that would cause it.

I appreciate any help you can provide.