2011 Chevrolet Avalanche Owner's Manual - Page 356

9-88 Driving and Operating An authorized GM dealer may be able to diagnose and repair problems with the trailer. However, any diagnosis and repair of the trailer is not covered under the vehicle warranty. Please contact your trailer dealer for assistance with trailer repairs and trailer warranty information. SERVICE TRAILER BRAKE SYSTEM - This message will be displayed when there is a problem with the ITBC system. If this message persists over multiple ignition cycles there is problem with the ITBC system. Take the vehicle to an authorized GM dealer to have the ITBC system diagnosed and repaired. If either the CHECK TRAILER WIRING or SERVICE TRAILER BRAKE SYSTEM message is displayed while driving the vehicle, power is no longer available to the trailer brakes. When traffic conditions allow, carefully pull the vehicle over to the side of the road and turn the ignition off. Check the wiring connection to the trailer and turn the ignition back on. If either of these messages continues, either the vehicle or trailer needs service. Conversions and Add-Ons Add-On Electrical Equipment Notice: Do not add anything electrical to the vehicle unless you check with your dealer first. Some electrical equipment can damage the vehicle and the damage would not be covered by the vehicle's warranty. Some add-on electrical equipment can keep other components from working as they should. Add-on equipment can drain the vehicle's 12‐volt battery, even if the vehicle is not operating. The vehicle has an airbag system. Before attempting to add anything electrical to the vehicle, see Servicing the Airbag-Equipped Vehicle on page 3‑40 and Adding Equipment to the Airbag-Equipped Vehicle on page 3‑40.