No communication (Obd2)/no start

2003 DODGE RAM
315,000 MILES • 5.9L • 6 CYL • 4WD • AUTOMATIC
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JOE FRAUENBERGER
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There is no power to Obd2 port. The truck cranks but does not start. My gauges (fuel, voltage, oil pressure, water temperature) do not seem to have signal. My overhead, display has power but shows (no Comunication). Any help would be great.
Feb 7, 2018 at 2:37 PM
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ASEMASTER6371
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Good evening.

Does the check engine light come on with the key on?

Check the fuse for the lighter. it sends power to the port.

Roy
Feb 7, 2018 at 3:24 PM
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JOE FRAUENBERGER
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All fuses are good. All the lights come on and stay on.
Feb 10, 2018 at 9:29 AM
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ASEMASTER6371
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pink wire, terminal 16 of the dlc is fed from fuse 51 in the underhood fuse block.

Make sure there is power on both sides of the fuse.

Roy
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Feb 10, 2018 at 12:26 PM
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JOE FRAUENBERGER
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there is power to data link connector. used three separate scan tools. no communication.
Feb 11, 2018 at 4:53 AM
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ASEMASTER6371
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you need to test the fuse in the diagram for power on both sides. if you have power the wire is broken between the connector and the fuse block.
If you have no power the issue is at the fuse block.

Roy
Feb 11, 2018 at 2:08 PM
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JOE FRAUENBERGER
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the wire is good the fuse box is good. there is power on both ends of fuse. what computer does the scan tool communicate with?
Feb 11, 2018 at 5:17 PM
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ASEMASTER6371
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So there is no power to pin 16 of the OBD port?

it communicates with all the modules through the serial data lines.

Roy
Feb 11, 2018 at 5:25 PM
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JOE FRAUENBERGER
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there is power, but no comunication to pin 16 ordered a new ecm, will see if it fixed it
Feb 18, 2018 at 7:24 AM
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ASEMASTER6371
  • ✓ASE Certified Mechanic
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If there is no power to pin 16, it will not communicate. that power is provided by the fuse block as I stated before. the pcm has no control over the power to pin 16. that powers up your device you are using to communicate.

Roy
Feb 18, 2018 at 7:33 AM
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