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2003 M1078A1 3126B 330 horsepower flash

Lostchain

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I would like to get a little more juice out of my engine while climbing grades.
Is it really as simple as flashing the ECU with a 5 Ton flash file? I have seen a few threads where people have mentioned having that done in concert with a gear change, but I haven’t found it explicitly stated and I don’t want to brick my ECU.

Is it known for a fact that there is no physical difference between a 2.5 ton and 5 ton 3126B ?

It just seems too easy, what an I missing?
 

fuzzytoaster

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You're missing the expensive CAT ET access, 70 pin patch cable, time investment, and risk of course. There are ways to make the process more cost effective but nothing short of experience can help you unless you've got a good CAT buddy and a case of beer.

Yes, the 3126 engine serials start with FMM and FML, both are physically identical engines.

If you take on the challenge you'll need to copy the parameters of your engine which is somewhat straight forward with CAT ET and some youtube videos. You'll be making a copy of its "personality module" which is specific to your engine. The 330 hp flash file is what CAT has under lock and key (for the $$$) and you'll need to obtain the right one. Our engines are made under the emergency/military/off-road use so it's crucial you get the right one otherwise your ECU will be looking for emissions imputs, code, then have issues.

It's important that you have the 70 pin adapter and plug directly into your ECM for these changes. The J1939 plug on the kickpanel can't handle the bandwidth to flash the ECM. You'll end up telling the unit to wipe and prepared to flash.. then you're stuck until you order a cable. Ask me how I know.

Changing the speedometer readout is easy and can be done through the j1939 connector. You'll need to know the count, which has been posted on SS a few times depending on the gears, and simply plug it in.
 

Keith Knight

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I have actually done this, but before this I had my 2003 M1078 at the CAT service for some code problems while there the uploaded my ECM data to a file with my name and engine serial number. After fixing all those code problems a year later the ECM died. During that year I had up graded the gears and added cruise control switches, Luckily they had my file on hand so I brought them my old dead ECM they ordered a new ECM and after lots of convincing the service manager agreed to up grade the HP to the 330 HP. He was reluctant to do it but after I explained it’s out of warranty anyway and the same engine he agreed. After I got the truck running again I drove back to CAT where the finished programming the cruise control settings and adjusted the speedometer settings so it reads the proper speed with the gears. What a huge difference best thing ever!
 

Lostchain

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It's important that you have the 70 pin adapter and plug directly into your ECM for these changes. The J1939 plug on the kickpanel can't handle the bandwidth to flash the ECM. You'll end up telling the unit to wipe and prepared to flash.. then you're stuck until you order a cable. Ask me how I know.

This was the "Gotcha" I was afraid of. So there is no way to flash via the kick panel? Can you provide some information on the 70 pin cable? Is it easily available? Do you want to sell yours?

Thanks for the info!
 

Lostchain

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I have actually done this, but before this I had my 2003 M1078 at the CAT service for some code problems while there the uploaded my ECM data to a file with my name and engine serial number. After fixing all those code problems a year later the ECM died. During that year I had up graded the gears and added cruise control switches, Luckily they had my file on hand so I brought them my old dead ECM they ordered a new ECM and after lots of convincing the service manager agreed to up grade the HP to the 330 HP. He was reluctant to do it but after I explained it’s out of warranty anyway and the same engine he agreed. After I got the truck running again I drove back to CAT where the finished programming the cruise control settings and adjusted the speedometer settings so it reads the proper speed with the gears. What a huge difference best thing ever!
This is great info, I was playing around in ET and it mentioned taking an "ECU Replacement" file. Now that makes sense based on what you are saying, I will be sure to pull that immediately just so I have it on hand in-case my ECU ever croaks.
 

fuzzytoaster

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This was the "Gotcha" I was afraid of. So there is no way to flash via the kick panel? Can you provide some information on the 70 pin cable? Is it easily available? Do you want to sell yours?

Thanks for the info!
They're commercially available through a popular auction website under " Bypass Breakout Cable for Cat 70pin ECM's Bench Tuning Harness ". You'll need a communications adapter to plug it into your laptop. The military uses DPA 3+ and DPA 4+ units for this.
 

Lostchain

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It's important that you have the 70 pin adapter and plug directly into your ECM for these changes. The J1939 plug on the kickpanel can't handle the bandwidth to flash the ECM. You'll end up telling the unit to wipe and prepared to flash.. then you're stuck until you order a cable. Ask me how I know.
I figured I'd give it a shot and SURE ENOUGH, exactly what you said would happen, happened. Imangine that.
Now CAT ET basically believes the ECM is blank, however it won't even try to flash now, it bombs out with an error code 98304 "The ECM is not responding to the service tool"

Once I have the 70 pin adapter in hand, was there anything special needed to complete the flash or do I simply try again while directly connected?
Thanks for the help.
 

fuzzytoaster

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I figured I'd give it a shot and SURE ENOUGH, exactly what you said would happen, happened. Imangine that.
Now CAT ET basically believes the ECM is blank, however it won't even try to flash now, it bombs out with an error code 98304 "The ECM is not responding to the service tool"

Once I have the 70 pin adapter in hand, was there anything special needed to complete the flash or do I simply try again while directly connected?
Thanks for the help.
You'll need to plug directly into the ECM and hook the harness up to 12v for it to power up. Unfortunately once the ECM is in this state you can't recover the trim settings or personality module which puts you in a pickle as it's specific to your engine. You'll need to get a copy from another truck as close to yours as possible and hope it functions correctly. If not then you'll have to pay CAT to "rebuild it" basically. :eek: I can share the trim file from my M1089A1 which is 330 hp factory but I can't be held liable if it doesn't behave.

You have to think of the hp flash file as an operating system of a computer. The trim/personality files are the drivers and apps that build on top of it. You'll need both for the engine to behave properly otherwise it will go into limp mode and have no throttle response.
 

Lostchain

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You'll need to plug directly into the ECM and hook the harness up to 12v for it to power up. Unfortunately once the ECM is in this state you can't recover the trim settings or personality module which puts you in a pickle as it's specific to your engine. You'll need to get a copy from another truck as close to yours as possible and hope it functions correctly. If not then you'll have to pay CAT to "rebuild it" basically. :eek: I can share the trim file from my M1089A1 which is 330 hp factory but I can't be held liable if it doesn't behave.

You have to think of the hp flash file as an operating system of a computer. The trim/personality files are the drivers and apps that build on top of it. You'll need both for the engine to behave properly otherwise it will go into limp mode and have no throttle response.

I believe that I successfully backed all of that up before the flash attempt. Did you remove your ECM from the truck when you used the 70pin cable?
To confirm what you said above, the ECM needs 12V? not 24?
 

fuzzytoaster

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I believe that I successfully backed all of that up before the flash attempt. Did you remove your ECM from the truck when you used the 70pin cable?
To confirm what you said above, the ECM needs 12V? not 24?
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. rofl
 

GeneralDisorder

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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. rofl
24v into 12v can work great for reviving starters that have been sitting for a long time and trying to turn over engines that have been dormant for many years. I've seen guys use that technique successfully. You must be careful and do it sparingly of course or shit goes downhill in a hurry.
 

coachgeo

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24v into 12v can work great for reviving starters that have been sitting for a long time and trying to turn over engines that have been dormant for many years. I've seen guys use that technique successfully. You must be careful and do it sparingly of course or shit goes downhill in a hurry.
Not relevant to situations with these trucks since starter is already 24v..... but in general...... ifff engine turns....... 24v will speed up the existing ability to turn of a 12v starter.... 24v on 12v, 36v on a 24v motor etc.. will NOT increase the torque/power.. only the speed. Which can be advantages at times. Diesels like to turn fast to start..

granted the extra, out of design juice will heat things up way faster..... so you should not hold the over juiced starter motor as long as you normally would risk..... and you have to let it cool off twice as long between bouts too.
 
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coachgeo

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"24v on 12v, 36v on a 24v motor etc.. will NOT increase the torque/power.. only the speed."

This statement is incorrect. It confuses induction motors with series wound DC motors (a starter).
???? learn something everyday... have been wrong before. Likely will again. yet. this seems opposite of everything have read about using 24v on 12v winches by competitive offroaders...... winch and starter motor are both DC so confused
 
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Ronmar

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Yea it kinda has to increase power/torque to increase RPM. Power output is a factor of the internal resistance and current flow which builds opposing electromagnetic fields, and the timing of the rotor and stator fields in relation to each other. With a given resistance, doubling the voltage quadruples the wattage. But most gains in torque are lost as soon as the increased RPM disrupts the timing...

So no real practical gains unless your goal is to warm up the motor and wear the brushes and commutator:)
 

coachgeo

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Yea it kinda has to increase power/torque to increase RPM. Power output is a factor of the internal resistance and current flow which builds opposing electromagnetic fields, and the timing of the rotor and stator fields in relation to each other. With a given resistance, doubling the voltage quadruples the wattage. But most gains in torque are lost as soon as the increased RPM disrupts the timing...

So no real practical gains unless your goal is to warm up the motor and wear the brushes and commutator:)
curious how this seems to not fit experience of competitive offroaders who use 12v winches at 24v..... same task asked of it..... just done faster .. and it is a race; fast is good in that case... but they also replace winch motors more often. Maybe the fast part they find an advantage is only in the spool in and spool back which is plausible??
 

Lostchain

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Wow did this one go off the rails……
yeah seriously…. Just an update, because I didn’t follow advice from @fuzzytoaster my truck is out of commission until a bench flashing harness arrives from Australia. Trying to flash the ECM through the vehicle harness is a BAD IDEA. ECM thinks it is blank and of-course I am now crank no-start. Luckily I took a full ECM replacement file download BEFORE I tried anything else, and the ECM is still detectable by CatET. I feel pretty good about completing the re-rate once the bench harness arrives.
 
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