[Turboeddiesel93]

Any help would be appreciated guys I have an 03 f350 7.3 it’s been down for almost 3 months took it on a 2.5 hour trip it ran perfectly fine went out the next morning to start it and it just cranks over batteries are draining quick tho replaced cps cleaned connections on under dash junction box I’m new to the diesel trucks but have tried all advice I’ve been told

 

[cjfisher]

Welcome to PSN! I have posted this on many threads:

"I would recommend that you first invest in FORScan (forscan.org) and a suitable adapter. I have an OBDLink EX usb adapter (should you wish to use a computer to collect data), or take a look at either a BAFX or OBDLink unit. Both BAFX/OBDLink have a bluetooth/Wifi units (there are a few folks around here that recommend them) that will would work with a smart phone (Run of the mill box store scanners and even a great number of the higher end scanners can't touch these trucks as Ford used the "heavy duty diesel" protocol for communication). Once you are setup I would capture data.. At minimum I would save RPM (really this is CPS), ICP, IPR, MAP, EOT and IVS (at least I think that is the PID for the go petal). FORScan will allow you to save the data as a .csv file which you can import into excel. The information you get from the truck will help identify what your problem really is without just "throwing parts" at the truck."

As this is a newer 7.3 the RPM gauge is not activated until the engine is running (97 and older would indicate RPMs while cranking) so you need something to connect to the PCM for information. It would be worth while to find and check the that the PCM and IDM are getting power. I don't have diagrams for the 98 and newer trucks. Hopefully, @Patrick Feeley will pop on shortly.

Cj

 

[sujumptd]

Hey there my friend, sorry your having issues. My initial thoughts on this would be to see if you can purchase (or not) the forscan or simply see if a friend has a simple OBD error code reader. This might get you started in the right direction and give you an idea of what may be going on. So we all have to start somewhere and I do remember my newbie days, anyway.....just an FYI 7.3's are driven by oil pressure (mostly), if there is no oil pressure your dead in the water. So I would investigate where the failure on oil pressure is happening. The ICP, IPR, and PCM work together to get this accomplished. Hope this gives you a starting point. Regards

 

[Bugman]

If your batteries are draining fast trying to start then it just may be the batteries, how old are they?

I'd put a charger on them and get them up to a full charge and see what happens. You can also get a digital volt meter and connect to them to see how far down the starter and glow plugs draw them when trying to start.

Cheep generic code readers will not work on these trucks. You need one that will work on a heavy duty diesel. Forscan is about the cheapest out there. Forscan lite is free to download onto a smart phone and then the adapter is around $30

 

[Patrick Feeley]

So much for shortly (just saw this)! Unfortunately, my diagrams only go up to 2001 and I don't know how close they are to a 2003. I could post the 2001 Engine Controls if desired. Cheers!

 

[cjfisher]

Patrick - IIRC the 2001 diagram should get him in the ball park as far as fuses go... I don't think Ford made any big changes after the 98 model year.

Cj