• Trailers require proper packing to prevent unsafe driving conditions.blue trailer image by Diana Mastepanova from Fotolia.com
  
  Highway safety isn't simply a matter of how a person drives. California has rules and laws in place to ensure that anyone pulling a trailer behind a vehicle does so without endangering other drivers. Trailer hitch laws include not only required components but also how drivers should install and use them to ensure that they perform at peak capacity.
  
  

Sway Control Laws

• Drivers must install a sway control device on a trailer hitch. This component allows the car and trailer to move together as a single unit. One type of sway control device, a friction bar, slides in and out with the motion of the vehicle. The weight of the trailer compresses the bar during turns, and this action compresses the trailer against the tow vehicle so they move together. The other type of sway control devices, dual-cam sway controls, work best with larger trailers carrying heavy loads. The cams help reduce the amount of sway in a trailer and also shift the weight forward when necessary.
  
  

Safety Chain Laws

• With the exception of fifth-wheel trailers, all vehicles towing a trailer must have a safety chain that connects the trailer to the hitch. This safety chain should have enough strength to maintain a connection between the trailer and the vehicle if a failure occurs in the hitch mechanism while the vehicle is in motion. The chain should be long enough to allow the trailer to turn without restriction but still short enough so that the coupler (the device that connects the trailer to the hitch) cannot touch the ground in cases of separation.
  
  

Breakaway Switch Laws

• California has required breakaway switches for any trailer with a gross weight of 1,500 lbs. or more since December 1955. A breakaway switch activates the trailer's breaks should it become detached from the tow vehicle. The driver connects the switch itself into the trailer's braking system via a wire running to a stationary part of the trailer hitch. If the two become detached (beyond the extent of the safety chain), the cable pulls a pin out of the breakaway switch, forcing the trailer's breaks to activate.
  
  

Trailer Light Laws

• Because trailers will often obscure the back of a vehicle, they require a fully working set of rear lights---tail, break and license plate. California also requires signal and clearance lights if the trailer obscures this portion of the tow vehicle. The electrical connection between the two vehicles occurs at the trailer hitch, so all drivers must ensure that the connectors are in working order before driving.