I have a 2003 7.3L excursion, that has left me stranded twice now. It periodically decides not to crank. I can start it in the morning drive to work, try to start it about an hour later and no start crank. Everytime this has happened the truck has full power, all lights and accessories work, fuel pump kicks on, even when I turn the key everything still have power, the light don't dim. I did notice when I hold the key down the odometer goes blank and if I hold the key down for longer then 5-10 seconds the air bag light starts blinking, this might be irrelevant to my problem but I thought I would mention it.

In the past when it hasn't cranked, I have removed all four terminals and cleaned them and it usually would start. Yesterday was not the case, it just wouldn't crank, I even recleaned the terminals. they batteries tested good. I tried jumping the starter but it wouldn't. I installed a new solenoid on the starter and it fired right up first crank. I restarted it three times last night it cranked and fire all three times. I did notice that I had to hold the key in the crank position longer than normal before the start would crank, about 3-5 second delay. the delay has been present before from time to time.

This morning the problem has come back, again full power, no crank. I have tried shifting it to neutral with no change. Does nyone have a clue what this could be? I am sure there are many possibilites. I have read the neutral safety switch could be out of adjustment, where is it located?

This evening I decided to swap starters, I had another starter that I know works so I put that one in. Before connecting the two cables (red power cable and smaller yellow cable) to the solenoid I checked the voltages. Both readings were equal to the batteries. Once the starter was hooked up, I tried to turn it over and nothing. All I would get is a click down at the starter. We hooked up some jumper cables still nothing. I tried it a few more times and it cranked and started. I shut it down after a minute, tried it again and nothing. This is so frustrating!

 

Here's a wiring diagram that shows a starter relay and the Digital Transmiswsion Range Sensor. The DTR is at the tranny.

 

if the motor is not turning what PaysonPSD says.

 

I decided to pull the starter out again and test it. Sure enough it was toast. I got a new one and all is good.

 

You beat me to it. I was just fixing to say starter