No crank issue, help please (solved)

[franklin2]

If this truck is a keeper, I would be looking on ebay for a used EVTM manual for it. Great diagrams. And when you make a discovery or want to make notes, you can do it directly on the diagram in pencil. Making your own notes on the diagrams really helps.

 

[Ziptie Mechanic]

I can't find a fuse box in any of the usual locations you'd find one in the cab?!??? Most vehicles have one on the outer side up under the drivers side dash area.... a few on the passangers and I have even seen them behind the glove box or the transmission "hump" / tunnel behind some plastic panels but I can't find anything in the cab?

 

[sgtsandman]

I seem to remember the fuse box being on the side of the dash, driver's side in my 1998. You had to have the door open in order to access the access panel. Maybe yours is there?

 

[franklin2]

 

[Ziptie Mechanic]

....Do you know how many times I over looked that...

Sooo in the diagram it says central junction box.... I am assuming the "24" is the fuse number since ford felt it not worth their time to label the fuses on the pannel door.... I'll report back.

 

[Ziptie Mechanic]

So fuse #24 in the cabin fuse box is fine, I replaced it anyway and then confirmed via the multi-meter that there was voltage passing through the circuit when the ignition ket was turned to start... clipped some alligator clipped wires to the leads, and to two insulated multistrand copper wires I just shoved into the little tiny female sockets for the mini fuse. It registered 3.5 volts which fell to 3.3volts pretty quickly then sat there. So I suppose that confirms the ignition switch is fine.

So then it's either the neutral safety switch or something in the wiring after the fuse block....right? I guess I could unplug the relays and shove the wires in it's sockets similarly as to what I did to check for voltage at the fuse... since my test light that works is missing and the other one I have needs a new bulb.....

 

[franklin2]

3 volts? You did not get 12 volts to ground? You could also jump 12v power to that fuse to see if it will crank. Just make sure you are in park and don't run over anyone.

 

[Ziptie Mechanic]

3 volts? You did not get 12 volts to ground? You could also jump 12v power to that fuse to see if it will crank. Just make sure you are in park and don't run over anyone.

Like what a 16 gauge wire from the positive battery terminal to the fuse? If it’s supposed to be 12v there what would cause it to be low but still present only when trying to crank?

 

[franklin2]

Like what a 16 gauge wire from the positive battery terminal to the fuse? If it’s supposed to be 12v there what would cause it to be low but still present only when trying to crank?

Poor dirty connection somewhere that has too much resistance.

 

[Ziptie Mechanic]

So I replaced the NSS, still wouldn’t start, rechecked voltage at fuse 24 though and saw. 6.7 volts… I figured I’d get my son up to the shop to turn the key while I probed the sockets for the relays… wrote down what I was seeing and it didn’t make sense to me why it’s not trying to crank I finally went.. is it possible I fixed the original issue but one of the relays I replaced is bad? Because I’m pretty sure the replacements are fake Ford parts as the originals are taller and don’t say Ford on them.

So I swapped one of the originals still in the fuse box under the hood to 56B, still no crank, moved it to 56A, it started!!! So then I played musical chairs with the relays to confirm, one of the replacements was bad, AND all of the original ones worked!?
So all I can figure is yes the NSS went bad but then I added a problem with swapping the relays for two eBay allegedly Ford replacements. I ended up putting all the original relays back and marked the bad one, going to tear it apart to see what I can about it just curious.

she’s starting and running now though so thanks to those who helped me figure it out

 

[SenorNoob]

Bad new parts strike again! Don't ya just LOVE that?