2012 International 7400 code spn077

[mekanik]

That's good the throttle plate needs to be open to start.

To reflash the ECM you need Navistar's NavCal software and connection to their mainframe
plus a laptop and a communication adapter. To manually reset parameters you need a laptop
with a Maxxforce compatible program and a communication adapter. The mass air flow sensor also
needs to be recalibrated.

Your scanner should give you a software version number at startup or there
may be another way of accessing it. Contact the scanner manufacturer support
phone number and see if you can get it updated if it needs to be.
Otherwise you need to get it scanned and see why it will not start. There could be a number of reasons.

 

[mattyt1984]

I finally go back to working on this truck. I had the dealer come out and scan it and they tell me the voltage going to the computer is only 2.6 volts and it should be 12 volts. He suggested looking for bad wiring. All wiring is good above battery and I have 3 brand new batteries and engine does crank over very good. Does anyone have wiring diagram to the ECM and of the ECM? I would like to test for voltage right at the input of ECM.

 

[mekanik]

Is the VIN you posted earlier correct? According to the VIN the engine is a Maxxforce DT inline six cylinder.
Is it a Maxxforce 9 or 10? I believe you previously posted it was a 7.4 or 7.6 liter engine.
The Maxxforce 7 is a V8.

 

[mattyt1984]

That is the correct VIN. It is a straight 6 cylinder engine

 

[mekanik]

There is a harness that comes from the batteries that supplies power to the engine ECM. International call it the clean power harness. It is notorious for rubbing through and having corrosion break the wires. There should be a fuse holder in the battery box with a 40 amp fuse in it supplying power to the clean power harness. It consists of three ten gauge wires two red positive wires and a white ground wire. there can be more than one three pin connector between the batteries and the main harness depending where the battery box is. you want to check the three pin plugs as well for expanded connectors.

Getting the connector off the engine ECM is a pain as its above the starter at the rear of the engine.

 

[mekanik]

There is a three pin connector in the main harness near the steering column where the clean power harness connects to the main harness. Follow it from the batteries and using the power and ground put a load on it. I use both filaments in a headlight bulb.

 

[mattyt1984]

I was not able to locate that harness it all appears to be in split loom conduit. I hate to keep cutting into it as the casing looks fine. Any other ideas on where to look. Do the power wires go to relays or fuses before ecm?