2014 Buick LaCrosse Owner Manual - Page 247

Driving and Operating Safety Chains Always attach chains between the vehicle and the trailer. Cross the safety chains under the tongue of the trailer to help prevent the tongue from contacting the road if it becomes separated from the hitch. Leave enough slack so the rig can turn. Never allow safety chains to drag on the ground. 9-69 Conversions and Add-Ons Add-On Electrical Equipment 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 3-30 and Adding Equipment to the Airbag-Equipped Vehicle on page 3-31. { Caution Some electrical equipment can damage the vehicle or cause components to not work and would not be covered by the warranty. Always check with your dealer before adding electrical equipment. Trailer Brakes Does the trailer have its own brakes? Be sure to read and follow the instructions for the trailer brakes so they are installed, adjusted, and maintained properly. Because the vehicle has antilock brakes, do not tap into the vehicle's brake system. If this is done, both brake systems will not work well, or at all.