Noob to the site in need of help

[dustys24valve]

Long story short my truck stopped running the other day out of the blue in my driveway. No power going to injection pump or external air dog lift pump. I can jump out relays for both and truck starts and idles only. All power and grounds to Ecm checked out good, evrything i tested pointed to bad ECM. Replaced it tonight and still have same GD issue..... I'm at a total loss right now and dont know which direction to go.......need ideas:banghead:It's a 2002 2500 24v automatic

[ISX]

Could you tell us any codes or what symptoms you were seeing that pointed to the ECM so we could be on the same page of your troubleshooting. More details you can give them quicker and better we can help.

[dustys24valve]

The only code that comes up is P1694....truck ran fine up until last week..it was just dead. I checked for power at all incoming wires to computer at the connection using diagrams found on this site as far as what wire from harness does what....everythin getting power...ohmed out computer grounds from harness to battery and checked continuity of said wires.....Tried to hook up a Snap on scan tool to OBD2 port and it wouldnt communicate with computer.....truck has come up with same code in previous checks when truck still running

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Does the ecm need to see a signal from crank position sensor before powering pump?

[Mopar1973Man]

P1694 http://articles.mopar1973man.com/2nd-generation-24v-dodge-cummins/59-obdii-error-codes/232-p1694-no-bus-message-received-from-companion-module You have communication problem with the ECM. I would check all the wire under the hood for a poor connection.