Mazda mazda3 2015 Owner's Manual page 147

Safety Chains
Safety chains must be used as a precautionary measure should the trailer become
unintentionally unhitched. They should cross under the trailer tongue and attach to the hitch.
Leave enough slack to allow full turns. Consult literature published by your trailer or hitch
manufacturer for more details.
Make sure the safety chain is securely attached to both the trailer and the vehicle prior
to departure:
Towing a trailer without using a safety chain securely attached to both the trailer and
the vehicle is dangerous. If damage occurs to the coupling unit or hitch ball, the trailer
could wander into another lane and cause a collision.
Trailer Lights
Do not connect a trailer lighting system directly to the lighting system of your Mazda.
This may damage your vehicle's electrical system and lighting systems. To connect the
lighting system, consult an Authorised Mazda Dealer.
Trailer Brakes
Check the Maximum trailer towing-load table in Weight Limits (page 3-61 ), and if your
trailer weight exceeds the value in the TOTAL TRAILER WEIGHT (Trailer without brake),
trailer brakes are required.
If your trailer has brakes, make sure they meet regulations.
Do not connect a hydraulic trailer-brake system to your vehicle's brake system:
Connecting a hydraulic trailer-brake system directly to the vehicle brake system is
dangerous and will result in inadequate braking and possible injury.
WARNING
CAUTION
WARNING
Before Driving
Towing
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