Hi everyone, I’ve got the motor in my bus up and running. Everything is running good, but I still have some small stuff left to clean up like the new battery cables and starter wiring etc.

Friday, I was making a list of all the things needed to be finished up to get this thing down the road. I plugged in FORScan looking for a code related to the OD light blinking on the shifter. Now I have a bunch of new codes along with what I assume is the trans issue.

P0743 -TCC circuit
P0380 -Glowplug circuit
P1139 -WIF indicator
P0541 -IAH circuit
B1868 -Airbag warning indicator

None of these codes were here after the engine rebuild btw. I plugged it in cause when I had the bus running last, The OD light was blinking and stayed blinking. Before, the OD light would blink and go away. Sometimes it came back sometimes it didn’t. But every time I looked for codes on FORScan after the engine rebuild there were no codes. (OD light has been blinking intermittently since I bought it 3yrs ago)

I am not worried about the B1868 code yet or the P0541 code…
(I deleted my IAH, and the airbag is probably due to the passenger airbag missing cause it’s a bus)

Anyway, I’m new to diagnosing these 7.3’s (except for when it’s a bad motor). To you more experienced 7.3 techs out there, where should I start with these codes? I haven’t looked in my factory manual yet, but I figured I’d bounce this off you guys first just to get some opinions and concerns rolling…
Really only concerned with the top 3 codes right now; P0743, P0380, P1139….


Let me know what you think. Thanks, -Chey

 

https://www.dieselplace.com/threads/...-po743.477625/

maybe this

 

I will look into that thanks

 

@Mark Kovalsky do you have any suggestions for his P0743 code?

 

Ok I dove into the P0380 code after work. Figured I’d test glow plug resistance first, considering the relay is working.

.6ohm across the board. Except for cyl 5. Tried continuity as well, continuity everywhere except cyl 5. Looks like I’m taking off a valve cover. Great.


EDIT I: I’m getting too quick working on the van chassis lol;
I Pulled the valve cover off, pulled the cyl 5 glow plug, checked resistance. .5ohms.

Reinstall glow plug, and its connector, check resistance at the valve cover connector, .5ohm-.6ohm across the board (including cyl 5.)

Reinstall valve cover, breakout FORScan, clear codes. P0380 still active next start up. Not sure where to go from here.. guess I’ll test the GPR.


EDIT II: I found a pinpoint test for glow plug system, including p0380

Glow plug system pinpoint test

 

P0380 is not a glow plug code. It is a glow plug relay control circuit code. What year and model are the engine and PCM out of? Are either of them CA emissions or are they federal?

 

I realize that when thinking things over last night. 2000 E450 7.3l. No California.

 

So I got into the service manual and found pinpoint test for the P0743 code.

I’m leaning toward replacing the solenoid pack and going from there.

Are the solenoid pack the same for all diesel 4r100’s? And where does one source this part from? Thanks in advance…

 

Ok, getting somewhere I think. Tonight I went through the glowplug pinpoint test. Got to where I should install a new relay (mine was brand new motorcraft) Swapped in my original GPR and cleared the P0380 code (for now, hopefully for good). Has yet to come back, unsure if it will be affected by x amount of run cycles….

where does one find the rest of the PC/ED pinpoint tests? Mainly for p0743 and p1139. Thanks in advance….
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Did you run the pinpoint tests, or are you just throwing parts at it until it's fixed?

When (not if) replacing the solenoid body doesn't fix it, run the pinpoint tests and that will find where your problem lies. I'm betting on a broken wire.

 

Thanks. I just took it to a shop for a diagnosis this morning. Hopefully they find something. If not, pinpoint tests here I come. Been overwhelmed at work and with life, so it seemed easier to have a shop do the diagnosing and pinpointing the issue.

at what point do I just call it and say I need a full overhaul or new trans??

also, this morning on the way to the trans shop. I got a new transmission code P0741…. Shifting sucks, banged into 3rd/4th gear last night. Also heard what sounded like the solenoid firing on its own when the truck was turned off last night.

fingers crossed

 

Shop diagnosed a bad connector plug/ pigtail. Paid for my diagnosis. Bought a pigtail. Down the road I go. I’ll check out the pigtail and swap it out most likely. Let’s hope this is what’s causing an issue….

 

If you could PM me the name of the shop you used.

 

Well, I installed the pigtail I bought. This is the pigtail for the transmission range sensor.

Unplugged all the connectors from the trans. Cut and butt each wire from the original trans range sensor connector to the new pig tail. Plug it all in. Fire up FORScan and I get a slew of other codes along with my original.

definitely feel like I’m going backwards. But determined to get to the bottom of this. Am I look at needing a new trans harness? Replace the remaining 3 pigtails? They do look pretty crummy too. I’m Confused….

enough fun for tonight, time for bed…

 

Range sensor? I don’t see how that could cause a P0741 code. My opinion is this would be related to the solenoid harness or connector. Same with the new codes popping up. Did you get the solenoid connector fully seated?

I would check the solenoid harness connector and terminals out very well.