Medium and Heavy Trucks
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Hi Kevin, My name is***** will be glad to try to help. What is the engine make ans model and chassis model of your truck? I can not look this info up by VIN unfortunately.
Here is the troubleshooting information for flash code 31. Let me know if you need more help.
SID is the system identifier. In your case it is Aux output 15. Aux outputs from the ecm are designated in the ecm programming. Do you have the Detroit software?.... Fmi is fault mode Id soch as open circuit... Short.... Data valid but out of range. Etc. I'm on the road but can follow up more when I get back
That fault is Aux.Output#15(E51)ShortToGround(HighSide). Your ECM output connector pin 51 which that output is for your engine brake harness. Inspect the harness and connector pins for damage and shorts rubbed through between the ECM connector and to the solenoids and harness under the valve cover. If the harness is ok you could have a shorted solenoid.
Pin 51 is at the ECM plug for jake hi... Here is a diagram.
Follow the wire from pin51 through the valve cover connector pins and to the jake solenoids for any rubbed through wires
Is your truck DDEC 5?
Thanks for the info. I know what you have now... Your problem is at output pin 51 but for your ECM that output is programmed for EGR. Click on this link and go to PDF page 12. Then go to PDF page 17 and you will see Pin 51 for Jake in the Vehicle Interface connector. Schematics
It would be the ECU connector which is an output.
you are correct
The EGR valve actually will vary in output voltage from the ECM to control its position which varies on the information from the other sensors the ECM is receiving. The fault is for a short either in the harness or the EGR itself. Inspect the wire from E51 to the EGR and run a test wire if you would prefer to see if the problem still exists. If so the problem is likely the EGR valve itself. They get carboned up and loaded with soot, then start sticking and can cause the electrical control side to fail. Using the Detroit software with a laptop is the easiest way to monitor live data for the EGR operation.