At central junction box fuse 18 (check your book location), pull the fuse.
Check for voltage with the ignition switch to Start position.
If present, the fault is further down the circuit toward the TR switch.
Replace the fuse and try starting again at the same time moving the trans selecter lever. If you get reaction then the Tr switch is suspect.
Find the starter relay with the heavey cables on it.
You will see a smaller gauge lead to a seperate terminal.
Remove this lead if you can't get a clean connection and apply battery on it.
If the circuit is good from that point on, the motor will crank.
These methods sectionalize for the fault location..

 

Thanks for the detailed response. This will really help me isolate the problem. I'll post again once I've gone through these steps.

-Bill

 

This morning the truck started just fine. Does this indicate that it's more likely to be a part sticking such as the starter relay?

 

I'm still having the same problem. I replaced the battery and then I replaced the starter relay. Now I don't have any power at all, just completely dead. I disconnected the battery before installing the removing the starter relay and hooked everything back up and then connected the battery. Now I get nothing - the alarm won't reset, nothing happens when I turn the key. Basically it's like a dead battery. Wow I'm confused.

 

On the starter relay is a single small lead that pulls up the relay thru the ignition switch. Use a voltmeter to see if 12 volts appears at this terminal when the ignition is in start position. It must be there to pull up the relay and pass power on to the starter.
Check the cables for being open.
There is not much there to miss.
Battery to starter relay, relay to starter.
Ignition switch to starter relay.
Power to ignition switch.
Ground cable.

 

If the starter relay clicks up with the ignition switch then the fault should be with the starter or it's leads.
The firewall starter relay passes power to another relay inside the starter that closes heavy copper contacts to pass the high current the starter draws.
Your problem has to be between those two points.

 

you guys ever solve this.. mines doing same thing now.

 

Can you post some info on your truck or complete your profile ?

Did you do the test above, if so what were the results ?

 

2001 supercrew. 4.6l. Gone thru everything like above posts. I have no power on little wire at firewall relay when ign. is in start pos. I can start truck with a screwdriver on that relay.

 

What was the result for testing the fuse ?

Have you tried starting the truck in Neutral ?

EDIT : Remove the PATS question, truck starts when the relay is jumpered.

- Have you tried applying power to the small wire on the starter motor relay ( not using a screw driver to jumper the Normally Open Contacts ) ?

 

I have a 97 f150 and a few days ago i was at the gas station and shut it off and I went to crank it back up and it wouldnt crank. the radio and all of the lights would come on,but after i turned it over all the way nothing from the starter and when i let off the key the door locks kinda jump up and down. I first checked my baterry posts. I took the cables off and cleaned the corrosion and even changed the negative with a new terminal. I then put them back on and there tight. I tryed jumpin it off nothing. i know the battery is good ttho,i just replaced it 3 months ago. i then got my cousin to pull me to the house. After i got it to the house,i walked inside for bout 15 min and came back out and it cranked right up. anyway i drove it for 3 days until today. I drove it to town and it wouldnt crank again and the same thing with the door locks. i used my keyless doorlock key and then left it alone for bout 15 min and it cranked right up. I drove it to the house now hear it sits will not do anything. Also I'm kinda leaning towards maybe its something to do with the antitheft keyless entry thing.ANYBODY OUT THERE HAVE ANY SUGGESTIONS? THEY WILL BE GREATLY APPRECIATED!!!!

 

First, the anti theft does not control cranking.
I would first start with the start solenoid located on the firewall.
Does it click when the issue is present?
If yes, do you hear the starter engage?
If yes, then the starter is suspect.
If no, otherwise there is some issue before the starter with the start solenoid or the cable/connections.
Always have a background though that there could be more than one issue causing confusion.
As for the battery, if it had a broken internal cell strap, it can act as you see because it will act the same as a bad connection anywhere in the circuit because it's a part of the same. The tipoff to this condition is the interior lights will go out when a load is placed on the battery and the voltage goes low.
There is no more to it than this path..
Comment: when the door locks do the jig, it's from low voltage either from a bad cable connection, heavy current contacts are burnt or even excess current draw that drags the voltage down..
The issue is there, you just have to flush it out.
Good luck.

 

Next time you can replicate the issue, also try shifting into Neutral and starting there.

The DTR ( digital Trans Range / "neutral" switch ) might be having an issue.

This is a quick test to see if it is a park only issue.

If it does not start in neutral another check would be to see if the Tan w/ red stripe wire have + VDC at it when the key is in the start position.

could be the no crank no start issue is with the DTR, and the other symptoms are another issue.

Might be worth having the battery load tested, just because it is 3 months old, does not make it good ( that is a guess, not a diagnostic test confirmed ).

 

I'm having this problem. Truck wouldn't start when i left work the other night. The solenoid makes a click when I turn the key over. I've switched out the battery with a brand new one, so it's not that. One time earlier when I attempted to start it, and removed the keys when it didn't start, the alarm suggesting the keys were still in the ignition stayed on after I removed them. There is no power is the S-wire that connects to the solenoid relay when the key is in start position.

 

I checked the fuses, and it won't start in neutral.