Can 20 Amp Fuse Replace 40 Amp Breaker on ETBC7L Installation

Question:

I have a 10 gauge wire with a 20 amp fuse that was connected to the battery to light a truck cap light. I no longer have the cap, and will use the connected battery wire to provide power to the black wire on the 7 pin trailer harness. The trailer harness came with a circuit breaker to be mounted in the engine bay before connecting the wire to the battery. Would the 20 amp fuse currently connected to the battery be sufficient if connected to the black power wire or should I replaced the fuse with the included circuit breaker? I will be using the Curt Echo Mobile Brake Controller. I have attached two photos of the wire connected to the battery with the 20 amp fuse. Thank you for the help.

asked by: Donald S

Helpful Expert Reply:

You can use that wire, but you will want to install the 40 amp breaker that came with your # ETBC7L. The Echo # C51180 won't pull that much power but the combination of the brake controller and the trailer would cause your 20 amp fuse to blow.

expert reply by: Robin H