What Size Fuse or Circuit Breaker Should be Used for Brake Controller on a 2006 Chevrolet Silverado

Expert Reply:

The reason you would not want to install a 30 amp fuse or circuit breaker in a 4 brake magnet application, when installing a Prodigy P2 brake controller, # 90885, is that the extra amperage required to break the circuit could cause an issue with the wiring on the trailer or vehicle because it would take longer for the circuit to spike to 30 amps. In applications with 6 to 8 brake magnets or more, more amperage is required to activate the brakes properly so the time for the amperage spike is shorter to break the circuit in a 30 amp circuit breaker or fuse, and does not present an issue.

For brake controllers we do not recommended that fuses be installed in place of circuit breakers. One reason for this is that an auto reset circuit breaker will reset if there is an intermittent short, once the short is no longer present on the circuit, and braking performance would be restored. With a fuse, once blown, braking performance is terminated until the fuse is physically replaced.

On your 2006 Silverado, the installation uses fuses under the hood, see brake controller installation article. For factory tow package wiring installations, fused circuits are typical. Chevrolet typically installs a 30 amp fuse at the power stud where the brake controller power wire is attached. Installing a 20 amp fuse in that location will protect your brake controller better as long as your trailers only have one or two brake axles.

expert reply by: Bob G