MK440 Bank 1 Red Light Help!

[NikLaw1]

I have a Minnkota 4 bank charger. I've always had bank 1 extended to charge a battery in the back of the boat

For the last 3 years it was ran with 18AWG wire I supplied. Today I re ran the leads with 12 AWG hoping it would allow more amps and faster charging. I cut the old wires out and ran the new 12 AWG. Turned it on and Red light! Polarity is correct (double and triple checked), inline fuse was removed though. Could the charge sense the absence of a 30amp fuse? Would is not like the 12AWG? I'm lost now

[CatFan]

Maybe a temperature sensor in the wire?

Get the fuse back in there or make sure you have good insurance.

[wmitch2]

I've been told and have read that you CAN NOT cut or shorten the original wires. You can extend them, but you have to have the ones there that it comes with. AND, you need the fuse intact. Somehow it reads the temp and resistance and then won't work if it's not the same. Also, when extending the wires, they must be of the same gauge.