You have removed the chip and/or tuner..Right? All wiring from the PCM to the solenoid has been checked and some wiring has been replaced (shift solenoid connector). All Ohmic values of the shift solenoid have been checked and are within acceptable ranges.
I have read while researching That if a problem arises with the shift solenoids or wiring to it (uncertain of those parameters) the vehicle will be forced into a LIMP MODE and this is for the vehicles own protection. My truck entered limp mode with the shift pack unplugged and yours acted better unplugged. And unplugged, yours showed no tranny codes. I think we have got this rat cornered. I think the voltage reading you took with Key On Engine Running at the shift connector is correct. That would open all solenoid controlled valves and leave EPC off to allow max flow of ATF. I hope you can get a PCM at a reasonable price. I have never changed one, not even sure where its at. All I do know and have heard is be careful when changing it. Good Luck and keep us posted. Sorry for your trouble. But Thankful at the same time.

 

G'day again AJ,
Just to clarify the Chip in Chip out. I have tried this testing with the chip in and the chip out and the results and symptoms were the same (it made no difference either way).
In fact the first thing I did way back when symptoms started the first thing I did was pull the chip and it made no difference in so eliminating the chip as a possible culprit.

So as I began to suspect the cornered rat is most likely the PCM?
I do have a likely replacement PCM out of an Aussie 2004 7.3 Powerstroke.
Going by the Part # it should be identical:
Original PCM in the truck Part#:
DPC-422 QHL2 EEC-V
1C3F-12A650-ARC (I think this is the critical Part#??)
S/N: MK9B7UE181Y2
G EE0FA 4C31E
The replacement PCM Part#:
DPC-422 QHL2 EEC-V
1C3F-12A650-ARC (again; I think this is the critical Part#??)
S/N: MK9B7UE7DRLZ
G EEFA 4D21E
There is a difference in the Serial # and I don't know what significance that is?
My truck is an Aussie 2005 Auto 7.3 and the replacement PCM is from an Aussie 2004 Auto 7.3.

So I will plug the tranny back in and see what the new connector has done. I don't suspect anything as the wiring had checked out ok before replacing the connector.
After that I'll disconnect batteries and swap out the PCM

Fingers crossed.

 

Some time later-update:
I finally found some more time to play with truck again.

So after plugging in the newly wired up connector and with no PHP Chip (stock) I ran the same test going through the gears.
Reverse, Drive, Reverse, 2nd, Reverse, 1st, Reverse, Drive, Park.
All the time the OD light continued blinking. Truck reacted close to normal through the first few reverse-forward and then started to limp a little.
I still get good RPM response to pedal in Park and Neutral
Shut her down and put AE over her and still only get P0603 and blinking OD light.

I need assurance that swapping out the PCM above is the next logical step

 

Yes sir, I believe the PCM is the next logical step. Especially if that P0603 code keeps coming back after being cleared.

 

You are 16.5 hours ahead of me. That should give you plenty of time to change out the PCM. But in all reality, take your time.

 

Well fellas we got that rat cornered and it didn't get away.

So I pulled my PCM and put in the one from the wrecking yard. Just plugged it in and sat it on the passenger side wheel (RHD).
I then put AE over KOEO and surprisingly, even though this PCM has just been powered up the first time in this truck, up pops P0603 Code.
I could only put it down to not being powered up for some time??
I then fully installed the PCM into its in vehicle location.
Next I fired her up and waited around 30 secs and surprise-surprise NO OD LIGHT BLINKING

So far so good; then went through the same procedure I'd done before with moving back and forth and gear changing.
She responded perfectly to pedal demands and still no blinking OD light .

Shut her down and put AE over it again. The only code was still that P0603

I then took her for a run of about 20Km. Hills, flats slow speed areas, high speed areas. All the while she performed perfectly.
Even put the Cruise Control through its paces. Works instantly and perfectly every time
Not once did the OD light start blinking
Got home and put AE over her and low and behold still that pesky P0603 Code

So we can all take a breather for now and I'll see how it goes for a while.

Cheers & Beers
Reg

 

Good job @Diesel Submariner . The case of the PCM has to be grounded to the cab. Did you remember to insert the little metal clip that touches the case that goes under one of the PCM bracket screws?

 

G'day Leonard,
It was a battle but got there in the end. Good support from AJ as well.

No I did not know about the case having to be earthed to the cab.
It worked without issue just sitting on the tyre when I first tested it on the truck.
I did have that little metal clip fall out when I pulled the PCM first up and didn't know where it came from?
I took her for that run today after seeing all was good and didn't have the PCM casing earthed out ..
It hasn't caused an issue I guess.
So I will ensure I fit that in the morning. Could it have anything to do with the persistent Code P0603

Cheers,
Reg

 

I think it might.

 

Oh well we'll soon know tomorrow after I put the clip in place.
Leaving it out when I started her and went for that run shouldn't have caused any damage .. well I hope not?

 

Diesel Submariner, That is Good News for sure. I've never changed a PCM. So this info is all new to me. The fella in Adelaide, can he test your old PCM if you have to take it back to him? It would be good info to have for future FTE. I do not know all possible P0603 Code parameters. I'm glad your back in the driver's seat instead of crawling all over this truck. If that old PCM had of effected a different part of the truck besides the tranny, I would not have been able to help. Enjoy. Send Caravan and boat/water pictures too.

 

https://autoservicecosts.com/obd2-codes/p0603/
I found this. Notice very last paragraph too. Interesting read, except all the advertising. p0603 might go away if you make sure to bond PCM to frame(negative battery post) A.K.A...…..the metal clip that came off the old PCM.

 

G'day AJ,

I can't give enough thanks to you and the other fellas for staying with me on this perplexing issue
The info on CODE P0603 is an interesting read. And as usual with electrical/electronic faults it can mostly be traced back to 'Grounds'.
I didn't in this case find any earth connection faults (not to say there isn't one).
Because of the amount of testing and pulling components I did, I don't recall when I actually first pulled the PCM out and that 'Grounding Clip' fell out (I didn't know where it came from at the time).
What I'm saying is I'm not sure if it fell out before or after I stated getting the P0603 Code?
Goes to show on a complex fault finding trial you should run a step by step diary of each process you go through. This is something I will adopt next time.

Anyway were back on the horse. I'll put that ground clip back in this morning.
I spoke to the fella in Adelaide about my faulty PCM and he want's it as a core return.
He has a contact in the USA who repairs the Aussie PCM. I will get a fault report from him and post it (it could take some time though).
I've also sent a report on this to Go Power Hungry Performance to see if the chip can be checked. Or could have been part of the cause (shaking lose and making cross contacts?? who knows).

I'll send a couple of pics on boat & caravan with the truck

Happy times & stay tuned.

 

Camped on Angarrichina Station

Chambers Gorge crossing

Crossing Parachillna Creek-2

Camped in Parachillna Gorge

Crossing Parachillna Creek-1

Rock Carving of the original Aboriginal Tribesmen of the area

Emu and Chicks around our camp


Camped at Farina Northern Flinders Ranges SA
The missus and I get out very remote in the Aussie Outback.
Hence the reason I need the truck to be in tip top shape. I have always done the maintenance and repair on my truck, it has never seen a Stealership (post warranty period) or other workshop other than mine.
Here are a few pics of a trip to the Flinders Ranges area in Northern South Australia. The caravan is a very sturdy Offroad/Rough Road van.
Fully self contained with plenty water solar power etc.
I'll dig up some truck and boat pics

 

Man, that looks awesome. I see two things wrong with these pictures .
1. Your steering wheel is on the wrong side of the vehicle.
2. I'm not in any of these pictures. Love it.