C1115 5A

WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Manual Trailer Brake Apply Request Switch Signal plausibility failure:

The ignition is turned from Off to On, the Manual Apply Switch is not activated, then it is detected that the Manual Apply Switch is activated for 5 minutes.
The fault is detected if the absolute value of the difference between the primary manual apply switch input, and redundant inputs exceeds a threshold for an extended amount of time.