Adding air braked trailer tow packages

NTEA fields fields questions on retrofitting air braked trailer towing systems to trucks that did not come with a factory tractor towing package. A key concern involves the requirement for an air-brake system (ABS) malfunction lamp on the dash of the towing vehicle (truck) to alert the driver of trouble. The center wire in a 7-pin electrical connector for an air braked trailer sends a signal to the tow truck, notifying the driver of trailer ABS system problems.