I have some questions about wiring on my 2003 f350, Aft of the battery on the passenger side is a solenoid, appears to be a starter assist relay. on the battery side of this relay, are 2 pair of gray wires, about 14-12ga, always hot. One pair constantly draws .68 amp from my battery, all the time, except occasionally it jumps to over 1 amp, and something whirrs for a second or two. With this disconnected, I have no power to the key switch. I'm considering adding another relay for this circuit, so it is only hot when I turn it on. Is this a common Ford trick???

 

If you're describing what I think you are that is the fusible link leading to your alternator, and yes that's the starter solenoid. There should also be a large gauge wire leading to your glow plug relay on that post as well.

 

Does this help you out at all?

 

yep, I left the glow plug link on there, because that relay is via the key and the pcm. I pulled the link for the alternator, and added another relay next to the start solenoid. I will feed that from the hot side of the solenoid with #4 tinned cable, and this relay will be acting as a battery switch to control that previously hot link to the alternator. I don't drive this truck often enough or far enough to allow this battery drainage. I was going to install a battery switch, but raising the hood to turn it on or off doesn't appeal to me, so I will control this relay from a dash switch. Thank you for the reply.

 

sort of, it looks like 026 is the link I am isolating.

thanks