Locating a Hot Wire, Key on only

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Jul 1, 2007 | 08:18 PM

Buckarcher

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From: Princeton, MN

Locating a Hot Wire, Key on only

I just bought an '08 6.4. I am transferring my work box from the old truck and need to hook up several wires, 3 hot all the time and one hot only when the key is on. These are all part of one harness. In the old truck when the manufacturer of the box installed it they hooked the key on only wire in with the PCM diode which caused me many troubles in more ways than one.

Can someone suggest a spot that is hot only when the key is on that is within a foot of an always hot connection and a ground?

Thanks,
Doc.

Jul 1, 2007 | 08:42 PM

99f350sd

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From: Lyndonville, Vermont

At the steering column you will find BIG wires going to it. Can't remember colors on my 99 but maybe white orange or yellow. There will be 2 or 3 of the same color comming from the key sw. These are acc wires.The input to the key sw hot all the time should be red. I usually clean about 1/2 of the wire insul with a razor,wrap another wire around it nice and solder and tape or liquid tape. I use a 12ga wire and then take off others from that one.

This is for an 06

12 VOLT CONSTANT YELLOW (+) and LIGHT GREEN/PURPLE (+) @ IGNITION SWITCH HARNESS
STARTER DARK GREEN (+) @ IGNITION SWITCH HARNESS
STARTER 2 N/A
IGNITION 1 RED/LIGHT GREEN (+) @ IGNITION SWITCH HARNESS
IGNITION 2 RED/BLACK (+) @ IGNITION SWITCH HARNESS
IGNITION 3 N/A
ACCESSORY/HEATER BLOWER 1 GRAY/YELLOW (+) @ IGNITION SWITCH HARNESS
ACCESSORY/HEATER BLOWER 2 DARK/BLUE/LIGHT GREEN (+) @ IGNITION SWITCH HARNESS
KEYSENSE N/A

Dick

Last edited by 99f350sd; Jul 1, 2007 at 08:46 PM.

Jul 2, 2007 | 03:57 PM

high ho silver

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From: Georgia

Check your manual. It should list a fuse in the fuse box under the dash that will do just what you want.

Jul 2, 2007 | 04:34 PM

Buckarcher

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From: Princeton, MN

I was hoping for something under the hood, not in the cab so I don't have to punch through a firewall. The wire hooks in just outside the back window, previously went down between the bed and the cab, along the frame rail and up into the engine compartment.

I'll look for a pass through though and see if it will reach.

Jul 2, 2007 | 04:50 PM

redford

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From: Stephensville WI

What about the harness for the trailer lights/brakes?

Jul 2, 2007 | 04:51 PM

function12

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From: houston

There is a hot wire the runs to the 7 pin trailer plug that is only hot with the key in. I used it for my air horn compressor. It run up the the engine compartment too.