2003 M1078A1 3126B 330 horsepower flash

[Wingnut13]

Bummer, I hope that cable shows up quickly for ya.

 

[Lostchain]

The ECM can stay on the engine. It is 12v. Only equipment (excavator, etc) are 24v. If in doubt putting 12v to a 24 system won't hurt it, it just won't power on. Put 24v on a 12v circuit and it will work great for a brief moment.

Just circling back on this point, according to the A1 schematic, the ECM is fed with 24v. I am assuming you were successful doing it with 12v and that is what I will try first, but this is interesting.

 

[coachgeo]

Just circling back on this point, according to the A1 schematic, the ECM is fed with 24v. I am assuming you were successful doing it with 12v and that is what I will try first, but this is interesting.

View attachment 884613

or is that just denoting the two 24v items out of the rest of the 12v ECM considering up above this there is a battery Pos and Neg feed into the ECM. with no voltage notation at all.... but one would assume a vehicle to usually be 12v..... those no notation needed???

 

[Lostchain]

or is that just denoting the two 24v items out of the rest of the 12v ECM considering up above this there is a battery Pos and Neg feed into the ECM. with no voltage notation at all.... but one would assume a vehicle to usually be 12v..... those no notation needed???

I just snipped out the connector part of the schematic to keep the picture small, but if you trace those all the way out they all end up at either +24 BATT or +24 Ignition(via circuit breakers). I will also use a volt meter at the truck connecter when I disconnect it for the bench flash just to confirm.

 

[coachgeo]

I just snipped out the connector part of the schematic to keep the picture small, but if you trace those all the way out they all end up at either +24 BATT or +24 Ignition(via circuit breakers). I will also use a volt meter at the truck connecter when I disconnect it for the bench flash just to confirm.

make sure to trace the other Pos and Neg to see where it goes as well... could well be the 24v connection is only a "sensing" thing the ECU uses to determine what ECU should do when there is/is not 24v. Its presence does not mean it powers the ECU. Pretty sure we do know it powers the TCU

 

[coachgeo]

Just circling back on this point, according to the A1 schematic, the ECM is fed with 24v. I am assuming you were successful doing it with 12v and that is what I will try first, but this is interesting.

View attachment 884613

waitttt.???. what???. you sure you got the right info here?????. there is a "CLUTCH PEDAL switch" in that list!!!!!

 

[Lostchain]

make sure to trace the other Pos and Neg to see where it goes as well... could well be the 24v connection is only a "sensing" thing the ECU uses to determine what ECU should do when there is/is not 24v. Its presence does not mean it powers the ECU. Pretty sure we do know it powers the TCU

What Cat Lists for those pins matches what the S&S schematic says. Which pin number were you suspecting was wired to +12 because I don't see any other pins wired to power in the schematic, they are all inputs and outputs.

 

[Lostchain]

waitttt.???. what???. you sure you got the right info here?????. there is a "CLUTCH PEDAL switch" in that list!!!!!

Like I said, I was trying to keep the pictures small. The full schematic is available for download if someone wants it, as you can see from the snip, Clutch is wired to PTO input further down the harness. ECM must use the clutch input for some part of its PTO programming.

 

[coachgeo]

What Cat Lists for those pins matches what the S&S schematic says. Which pin number were you suspecting was wired to +12 because I don't see any other pins wired to power in the schematic, they are all inputs and outputs.


View attachment 884638

gotcha.... miss read those two as one Pos and other Neg.

 

[Lostchain]

So to close the loop on this thread.
First, on the subject of performing the flash from the in-vehicle harness. I had originally used a wireless adapter (WDS-D) which is essentially a Wireless J1939 adapter. This unit was unable to flash the ECM and after bombing out, left the ECM in a "Blank Box" state, meaning that the only thing CAT ET would do is try to re-flash the ECM, which of-course, would fail again. I proceeded to order a 70 Pin bench flash cable, but it was manufactured in Australia and ended up getting a little hung up in customs. Meanwhile I had ordered the previous generation ICE Diagnostic kit that are starting to hit ebay for really cheap, and these are completely wired units. So I took out the *WIRED* Dearborn Protocol Adapter III Plus (DPA3+) and hooked it up to the truck, flashed the ECM no problem!! After having the truck down for 2 weeks and not knowing if I fried a $4700 ECM; to say I was relieved is an understatement.

So after having successfully flashed the ECM to 330HP, 2 codes were now set in the ECM. One was a code for a Barometric Pressure Sensor voltage high, and the other was related to the personality module code not being set. This is where the version of CAT ET I had let me down. To set the Personality Module Code after a re-rate, you would normally be prompted to enter a factory password. Well it turns out certain versions of CAT ET that are provided to customers (not dealers) are not allowed to use factory passwords. At this point I just wanted the truck running again and so I re-flashed to the 275HP flash file and fired up the truck. Took it for a cruise and it ran fine, no harm no foul.

I still wanted the 330HP tune so I was finally able to get a tech at the local CAT dealership that was willing to look into it for me. It turns out the 330HP Tune is actually the same PEAK torque as the 275HP Tune and so CAT doesn't charge the dealership for the re-rate fee! So the dealer was able to re-rate my engine for basically just 2 hours of shop time. I will note that the CAT Tech also used the in-vehicle harness to do the flash. Circling back on the barometric sensor code, the 330HP Tune also makes use of an atmospheric sensor that the 275HP does not. Luckily the CAT dealer had the sensor in stock and the harness already had the connector right there capped off, so it was truly plug and play.

On my trip home I added over 10mph to a hill climb that normally bogged the 275HP tune down to less than 35MPH. Best $518 bucks I ever spent!! Can't wait to try that hill towing my M1082!!

So for someone that really wants to try this themselves:

1.) Before doing ANYTHING else, pull an ECM Replacement File.

2.) Make sure you have a dealer version of CAT ET and you have a password generator.

3.) Make sure you have a copy of the original personality module flash file from CAT that is loaded in your ECM (you cannot pull it out of an existing ECM), in case you need to revert back.

4.) Get a WIRED J1939 Adapter

5.) Get the Barometric Sensor.


Good Luck!!

 

[fuzzytoaster]

Do you have the part number for the barometric sensor? I'm glad you got it working again. The 330hp really wakes it up!

 

[Lostchain]

Do you have the part number for the barometric sensor? I'm glad you got it working again. The 330hp really wakes it up!

The invoice has it as “194-6722 SENSOR GP-PR”
And they charged $218.85 for it. My truck is a 3126B, I didn’t research if the C7 will need it or maybe already has it.

https://parts.cat.com/en/catcorp/194-6722