Vehicle is equipped with factory integrated trailer brake control (itbc). Back in Jan., 2011 I got a message in the driver information center (dic): It said "service trailer brake system". message intermittent at first, and then more frequently, and then message appeared at start-up every time. Dealer fixed problem. In April of 2013 the same problem has returned in exactly the same pattern as the previous fault. This a faulty system at best, and has serious design flaws. The serious safety issue here is: When the "service trailer brake system" message appears on the dic; all trailer braking is lost. There is no default or back-up system in which to apply trailer brakes. Even the manual trailer brake control built into the itbc is also rendered inoperable. This itbc failure could happen at any time, and at any speed. This vehicle is rated to tow a trailer of 10,000lbs. Plus. Many peoples lives could be put in jeopardy if suddenly all trailer braking were lost on a steep downgrade. This itbc system needs to be re-designed so that a vehicle operator can operate the trailer brakes manually if automatic trailer brake control is lost when the operator gets a "service trailer brake system" on the dic.

- Sidney, ME, USA

The contact owns a 2007 GMC Sierra 3500. While driving 45 mph the brake light warning and the ABS lights illuminated on the instrumental panel. The headlights began to flicker; however, after shutting the engine off and checking under the hood the contact was unable to diagnose the failure. When he restarted the vehicle the brake light shut off and without warning, the transmission began to shift up and down at will. The dealer stated that the computer did not register any failure codes. The dealer also stated that if the failure recurred to allow them to diagnose the failure before shutting the engine off. The VIN was not available. The failure mileage was 12990 and the current mileage was 13050.

- Shippenville, PA, USA