Thanks, I'll start looking for shorts. Is that the box under the driver side by the side under the dash? Where some folks put in the chip? Not me though, it's never been chipped, I think?

 

that im not 100% on but i believe the PCM is bolted to the drivers side fender under the hood, i haven't ever messed with mine. but that sure looks like a PCM under the hood right there by the big under hood fuse box. the ones at work bolt to the motor themselves (Detroit)

 

That is the IDM. The pcm is behind the ebrake. You can see the plug in at the bottom of the firewall right above the inner fender.

PO: what number fuse was blown?

 

Fuse "U" according to that diagram.

 

anybody have a wiring diagram? This cruddy book I have doesn't seem to, for a diesel anyway. It would have to be a pretty good short to blow a 30 amp fuse, I would think? One question. Is it possible to test the glow plugs to see if they are hooked up and working without removing the valve covers? Could I use a DC inductive clamp meter and check the amps each side is pulling? Anybody have an idea, what they should pull? per side? Or all together? Could one of those blow that fuse? Probably not, it looks like they are on a straight shot from the battery. But, just wondering.

 

That fuse is #22 which powers the PCM relay, glow plug relay and fuel filter heater. It is blowing probably because the fuel filter heater is shorted, a common issue. Unplug the fuel heater wire, second connection from top on drivers side of the fuel filter canister, tape the wire up good, replace the fuse and fire it up. You can replace the fuel heater element at a later date if you want to, most just leave it unplugged.

 

Fuse U is also known as fuse #22, which energizes the PCM, the fuel filter (not "line") heater and the _coil_ circuit of the glow plug relay. Extremely common failure - the heater shorts out, blows the fuse, the truck won't start. The heater was designed into the filter bowl at a time in history when diesel fuel was not NEARLY as stable at low temperature as it is now. Nowadays, if you have winter blend fuel available, and esp. if you take the "belt and suspenders" approach of adding an anti-gel additive, you can do without the heater. Folks well "north of the border" do fine without it. So before replacing the fuse, disconnect the heater. It's a single-wire flat terminal connector on the driver's side of the bowl, red/green wire.

Glow plug test - disconnect a UVCH connector; the two outermost pins on the connector on the gasket go to the two corresponding glow plugs. Set your meter on lowest range of resistance, red probe on one of those pins, black probe on ground (battery neg). Resistance should be about 1 ohm. Repeat for all eight. If any read significantly higher (> 2 ohms), those GPs aren't working sufficiently; if any read "open" (infinite resistance), those GPs are shot, or the wiring under the valve cover is damaged.

There isn't "a" wiring diagram. There's a whole book of them. It's called the Ford factory EVTM - Electrical and Vacuum Troubleshooting Manual. If you want to DIY anything electrical on these trucks, it's strongly suggested to get one.

 

7 gps are wide open, bad for sure. 1 reads .3 ohms figure it's trash too. Connectors are burned on 3 of the gp terminals. Do I have to replace the whole conn?

 

And can they be bought?

 

Yes, they can be bought, try riffraft.

 

Found that site. Riffraff has a lot of good stuff. Diesel parts are high! Ouch! 39.00 for a connector. Hate to see what ford charges for them.
As far as glow plugs, stick with motorcraft? Or what brand should I use?

 

Motorcraft ZD11 are the plugs you want.

 

You might as we'll change the under valve cover gasket/harness when you change plugs Orielly sells Dorman valve cover gaskets/harness and they come with the connectors as we'll as gaskets

 

The Dorman solutions for this have a spotty record.

 

Are you saying, not of good quality? Gaskets? Connectors? or both?