Engine cranking without key

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Oct 9, 2008 | 08:13 PM

jdehn

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Joined: Aug 2006

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Engine cranking without key

Hi I have 2000 F250 with a 5.4L engine. I have a crazy problem I'm trying to trace. Yesterday I was sitting in the house and heard my truck cranking. I had to unhook the battery to get it to stop. I reconnected the battery today to check it out and I found that the ignition signal wire on the solenoid has a constant 12 volts. If I'm not mistaken this wire should only have voltage if the key is turned to the start position. After finding this I figured it had to be the ignition switch so I unhooked the switch and still have power to the signal wire. I checked the voltage on the plug for the switch and all the wires have power to them. It seems to me like there may be some type of short in the wiring. We have gotten alot of rain the last couple days and I'm wondering if water could have possibly gotten into something and caused a short. I'm not sure where else to check right now. Thanks in advance for any help.

Jason

Oct 9, 2008 | 08:25 PM

Franklin2

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Joined: Jan 2001

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From: Virginia

If you do not have some sort of remote starting system wired in, the next best guess is the wiring to the neutral safety switch underneath the truck. There are some hot wires usually bundled with these wires going to the switch on the tranny, and if they get near the exhaust, they can melt together and put voltage on the neutral safety circuit. The neutral safety switch is the last stop before the circuit heads to the solenoid.