I have a multi-mount winch for my '99 XJ. I currently have the winch wired through an Andersen plug on the front bumper for quick disconnects. The Andersen plug also mates to a set of 20' jumper cables. I don't like having a large gauge wire set directly hooked to the battery at all times. I picked up a 500amp (constant) 12v isolation relay for the project.
I came up with this diagram, and wanted to shoot it across you folks.
The idea is to trigger the isolation relay, and energize the winch (+) line only when the Ext Idle switch is engaged. I will never be jumping or winching without the idle switch on anyway, so it seems to be a logical idea. I will be wiring the hot lead of the trigger through a 10amp feed out of the PDC. The relay instructions say it will draw as little as 1amp when engaged, so I am not too afraid of popping fuses when I flip it on.
My fear is the 12v from the trigger circuit back flowing up into the ECU for some reason or another. Is this something I should fear, and soldier in a diode to prevent this from happening? What voltage flows up/down the Ext Idle circuit? Or am I just over thinking this and should just follow the pictured diagram (with the added fuze on the trigger line)?
I came up with this diagram, and wanted to shoot it across you folks.
The idea is to trigger the isolation relay, and energize the winch (+) line only when the Ext Idle switch is engaged. I will never be jumping or winching without the idle switch on anyway, so it seems to be a logical idea. I will be wiring the hot lead of the trigger through a 10amp feed out of the PDC. The relay instructions say it will draw as little as 1amp when engaged, so I am not too afraid of popping fuses when I flip it on.
My fear is the 12v from the trigger circuit back flowing up into the ECU for some reason or another. Is this something I should fear, and soldier in a diode to prevent this from happening? What voltage flows up/down the Ext Idle circuit? Or am I just over thinking this and should just follow the pictured diagram (with the added fuze on the trigger line)?
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