Hooking up high idle w/upfitter switches
Senior User
Joined: Dec 2007
Posts: 206
Likes: 0
in the last few days we've wired up 4 f350's without a problem except one. it's a 06 with manual trans and a service body with picker. he had already used switches 3&4 so I used #1 (30amp) and used the bcp ( purple ) wire because the orange wouldn't work ( because of the service body?). it idled up to 1400 rpm right off the bat and held it for almost an hour, then he found it idling up to 2000rpm. why is this? too high of amp on switch? or is there something I missed? also, on the 2009 we're working on, I can't find the upfitter harness. any secrets here?
Hotshot
Joined: Aug 2006
Posts: 17,398
Likes: 317
From: Whittier, CA
in the last few days we've wired up 4 f350's without a problem except one. it's a 06 with manual trans and a service body with picker. he had already used switches 3&4 so I used #1 (30amp) and used the bcp ( purple ) wire because the orange wouldn't work ( because of the service body?). it idled up to 1400 rpm right off the bat and held it for almost an hour, then he found it idling up to 2000rpm. why is this? too high of amp on switch? or is there something I missed? also, on the 2009 we're working on, I can't find the upfitter harness. any secrets here?
Second, the purple wire is for Battery Charge Protect, and will idle up to 1,200 or higher to protect the battery. If for some reason the battery is losing charge, like a marginal alternator for example, or perhaps something drawing a lot of current, then the RPM will go higher to maintain the charge. Was there something in use on the truck? Like lights or inverter?
Fleet Owner
Joined: Mar 2003
Posts: 24,724
Likes: 74
From: Blue Hill Township
The orange wire didn't work on my 07 either. I had 12VDC on the PTO wire. I hooked up the high idle on an 05 1 ton at a friend's farm and that one worked just fine using the orange wire. My 07 is an automatic.
Elder User
Joined: Sep 2004
Posts: 543
Likes: 0
From: Northern VA
I just finished this project on my 09 F350. I used upfitter 4 and spliced into the BCP (battery charge protect) wire. I plan to use it when running high electric loads like my electric winch and other things when connected to my race car trailer. It was as easy as connecting two wires. Nice! Might try using it to warm up the truck on a cold day, too.
New User
Joined: Nov 2006
Posts: 12
Likes: 0
From: greater houston area
i want to do this but have a manual trans. zf6. i have read all post on this mod and understand it all. except for the part about it not working on a manual. some one mentioned using a resistor or something. what's that about how do i do that?
Senior User
Joined: Nov 2008
Posts: 410
Likes: 0
From: Norfolk, VA
Are my brake lights supposed to come on? I flip my switch on and the truck idles ups but no lights. Should they come on?
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Hotshot
Joined: Aug 2006
Posts: 17,398
Likes: 317
From: Whittier, CA
New User
Joined: Jan 2007
Posts: 18
Likes: 0
From: Alberta, Canada
High idle on a 2010 F450 King Ranch
Just wondering if the same apply for my truck, I work in Northern Canada and I want to be able to let it idle for long period of time. Can anyone help.
Thanks
Thanks
Hotshot
Joined: Aug 2006
Posts: 17,398
Likes: 317
From: Whittier, CA
Hotshot
Joined: Aug 2006
Posts: 17,398
Likes: 317
From: Whittier, CA
Jimmy, I don't have remote start, but since no one jumped in I will reply. I know there have been guys with RS who have done the high idle. I don't think there are any problems with that. You just have to make sure you leave the truck in Park with the parking brake set. Once the truck starts, after a short delay, it should go high idle.