Help!! Truck won't pass SMOG

[Bloom99cummins]

I went to smog my truck in CA and when the tech plugged in to the OBD2 his computer could not communicate with my truck. He asked if i had a tuner or something on the truck. After 3 shops all unable to read the OBD2 i am left scratching my head. Would flashing ECM or PCM help? Need to pass ASAP!

The truck has never been tuned. but did have the ECM reflashed in 2019 by Auto computer specialists

 

truck runs great. no codes. Any help would be great. 

[TFaoro]

Do you own a code scanner where you could attempt to connect to the system? 

Edited February 7, 2020 by TFaoro

[ColoradoColt]

Fuse?

[pepsi71ocean]

Check the condition of the obd2 port.  My 99 stopped working and I needed to replace the pins with a pig tail obd harness. 

[Mopar1973Man]

14 hours ago, ColoradoColt said:

Fuse?

IOD fuse covers that plug. So if the interior lights work the plug has power. The ground is in the key panel if the headlights work the the ground it good. Beyond that is pure communication pins.