PACCAR PX-6 CM2150 (2007-09) Fault Code: 2554 PID: 131 SPN: 1209 FMI: 2 Exhaust Gas Pressure – Data Erratic, Intermittent, or Incorrect. The exhaust gas pressure sensor is reading an erratic value at initial Key On.

Verify the electronic control module (ECM) calibration is correct. Check the calibration revision history found on QuickServe™ Online for applicable fixes to the calibration stored in the ECM. If necessary, calibrate the ECM. Use the following procedure in the corresponding Troubleshooting and Repair Manual for the engine being serviced.

At KEY ON, before the engine starts, the sensor readings for intake manifold pressure, barometric air pressure, and exhaust gas pressure are compared to each other. This fault code occurs if the exhaust gas pressure sensor reading is different from the other sensor readings. This check is only done once after the keyswitch is turned ON.

Possible causes:

1)A stuck in-range exhaust gas pressure sensor reading
2)A high resistance in the exhaust gas pressure sensor signal or return lines
3)Plugging or restriction in the exhaust gas pressure sensor tube.

Possible repairs:

1)Replace the exhaust gas pressure sensor.
2)Repair or replace the engine harness.
3)Clean or replace the exhaust gas pressure sensor tube.
4)If necessary, calibrate the ECM.