Verify the 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. Reference the following procedure in the corresponding Troubleshooting and Repair Manual for the engine being serviced.
The aftertreatment sensors share a common ground wire with the coolant level sensor. Fault codes or problems related to the coolant level sensor and its ground circuit could potentially cause this fault.
1)Coolant level sensor and/or coolant level sensor ground circuit fault codes or related problems
2)Stuck in-range aftertreatment diesel oxidation catalyst inlet temperature sensor
3)High resistance in the aftertreatment diesel oxidation catalyst inlet temperature sensor signal or return lines
4)A miswired OEM harness
5)A face plugged or damaged aftertreatment diesel oxidation catalyst.
1)Replace the aftertreatment diesel oxidation catalyst inlet temperature sensor.
2)Replace the aftertreatment diesel particulate filter inlet temperature sensor.
3)Repair or replace the OEM harness and/or the aftertreatment harness.
4)Clean the aftertreatment diesel oxidation catalyst.
PACCAR PX-8 CM2150 (2007-09) Fault Code: 1666 PID: SPN: 3241 FMI: 3 Aftertreatment Exhaust Gas Temperature 1 Circuit – Voltage Above Normal or Shorted to High Source. High signal voltage detected at the catalyst inlet temperature sensor circuit.
PACCAR PX-8 CM2150 (2007-09) Fault Code: 1665 PID: SPN: 3241 FMI: 4 Aftertreatment Exhaust Gas Temperature 1 Circuit – Voltage Below Normal or Shorted to Low Source. Low signal voltage detected at the catalyst inlet sensor circuit.
PACCAR PX-8 CM2150 (2007-09) Fault Code: 1664 PID: SPN: 3050 FMI: 11 Catalyst Missing – Condition Exists. The aftertreatment catalyst in the exhaust system is not present.
PACCAR PX-8 CM2150 (2007-09) Fault Code: 1663 PID: SPN: 3241 FMI: 11 Catalyst Inlet Temperature Sensor Swapped with Outlet – Condition Exists. The inlet and outlet catalyst temperature sensor connections are swapped.
PACCAR PX-8 CM2150 (2007-09) Fault Code: 1242 PID: 91 SPN: 91 FMI: 2 Accelerator Pedal or Lever Position Sensor 1 and 2 – Data Erratic, Intermittent, or Incorrect. Accelerator position sensor number 1 and number 2 are reading different values.
PACCAR PX-8 CM2150 (2007-09) Fault Code: 1241 PID: None SPN: 2623 FMI: 4 Accelerator Pedal or Lever Position Sensor 2 Circuit – Voltage Below Normal or Shorted to Low Source. Low voltage detected at accelerator pedal position number 2 signal circuit.
