See also:

Driving Safely with a Trailer
Things You Need To Know Before Towing a Trailer Have the trailer properly serviced and keep it in good condition. Make sure that all the weights and load in the vehicle and trailer are within limit ...

Charging the Battery
Disconnect both battery cables to prevent damaging your vehicle’s electrical system. Always disconnect the negative (–) cable first, and reconnect it last. ...

Checking the Battery
Check the battery condition monthly. Look at the test indicator window and check the terminals for corrosion. If your vehicle's battery is disconnected or goes dead:  - The audio system ...