04 F150 FX4 no start
Thread Starter
Junior Member
Joined: Dec 2013
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From: Lake City, FL
My truck is equipped with a silencer under dash key which is a little black thing that plugs in under the steering wheel. I'm not sure if it's factory or aftermarket but if it's unplugged it kills power to the starter and the truck will not start or even crank. Maybe you have one. I didn't know what it was when I bought the truck I found out about it after going to a car wash and one of the dudes must have moved it and my truck would not start I started freaking out a little thinking they f'ed something up. The main guy there asked if there was an aftermarket security system and that's when it clicked for me to check that little black thing under the dash and boom it was all good. My truck is also an 04 fx4 screw. You could have a battery problem if odb isn't connecting. There is also the inertia switch that shuts the truck down in case it's flipped.
Senior Member
Joined: Mar 2013
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From: NJ
What about checking the fpdm? It's located above the spare tire on the frame. It's very common that it craps out and when you check it you'll know it will most likely be corroded. I replaced mine like 5 months ago it cost like $50 and takes minutes to replace.
Thread Starter
Junior Member
Joined: Dec 2013
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From: Lake City, FL
I checked that this morning and it didn't appear to be corroded. If anyone knows how to physically bench test the fdpm, dtp, and pats, that would be great info since I hate just throwing parts at a problem not knowing for certain if that part is actually the issue.
poopin.....on this thread
Joined: Sep 2010
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hmmm...have you tried unplugging and replugging the 3 power plugs into the ECU? Make sure that you have the neg side of the batter off when you do this.
Have you inspected the positive and negative battery cables beyond just the battery connection point. My brother recently had corrosion within the sleeve of cable and that caused intermittent starting. Replaced the cable and all was well.
on an olds intrigue that I had on college also had a loose connection on the back of the radio, that I had never touched or taken out, that caused some starting problems. Just unplugged and replugged it in, problem gone. But the security system ran through that thing, not sure that our trucks are the same.
long shots on all, but figured they might be worth a try.
Have you inspected the positive and negative battery cables beyond just the battery connection point. My brother recently had corrosion within the sleeve of cable and that caused intermittent starting. Replaced the cable and all was well.
on an olds intrigue that I had on college also had a loose connection on the back of the radio, that I had never touched or taken out, that caused some starting problems. Just unplugged and replugged it in, problem gone. But the security system ran through that thing, not sure that our trucks are the same.
long shots on all, but figured they might be worth a try.
Junior Member
Joined: Nov 2011
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did you read anything or just spit garbage out. it doesn't crank, the fpdm only runs the fuel pump. to check power you can just pull an injector plugin and see if red wire has power when key is on. it is same source of power the the computer gets.
poopin.....on this thread
Joined: Sep 2010
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wow harsh...not saying he is right or wrong...because I do not know, but is it possible that there could be enough corrosion that it could be causing a fault that would keep the computer from allowing the starter to turn over? I do not know, just asking.
Thread Starter
Junior Member
Joined: Dec 2013
Posts: 15
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From: Lake City, FL
hmmm...have you tried unplugging and replugging the 3 power plugs into the ECU? Make sure that you have the neg side of the batter off when you do this.
Have you inspected the positive and negative battery cables beyond just the battery connection point. My brother recently had corrosion within the sleeve of cable and that caused intermittent starting. Replaced the cable and all was well.
on an olds intrigue that I had on college also had a loose connection on the back of the radio, that I had never touched or taken out, that caused some starting problems. Just unplugged and replugged it in, problem gone. But the security system ran through that thing, not sure that our trucks are the same.
long shots on all, but figured they might be worth a try.
Have you inspected the positive and negative battery cables beyond just the battery connection point. My brother recently had corrosion within the sleeve of cable and that caused intermittent starting. Replaced the cable and all was well.
on an olds intrigue that I had on college also had a loose connection on the back of the radio, that I had never touched or taken out, that caused some starting problems. Just unplugged and replugged it in, problem gone. But the security system ran through that thing, not sure that our trucks are the same.
long shots on all, but figured they might be worth a try.
Senior Member
Joined: Mar 2013
Posts: 307
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From: NJ
Wow awesome, I'm trying to help the guy, I read it all. There's no need to be a jerk.
Thread Starter
Junior Member
Joined: Dec 2013
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From: Lake City, FL
Pulled an injector plugin and checked for power at the red wire and got nothing. so the computer system is intermittently (now more often than not) is not getting power... what could be the cause of such an intermittent issue?
poopin.....on this thread
Joined: Sep 2010
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Damn...do you have a buddy you could swap out ecus with just to see what happens?