PACCAR PX-8 CM2150 (2007-09) Fault Code: 238 PID: SID 232 SPN: 3511 FMI: 4 Sensor Supply 3 Circuit – Voltage Below Normal or Shorted to Low Source. Low voltage detected on the +5 volt sensor supply circuit to the engine speed sensor.

Description

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, recalibrate the ECM.

The ECM monitors the voltage level on the engine speed sensor +5 volt supply circuit. If the voltage falls below a limit which can be calibrated, then this fault is recorded.

Possible causes:

1)Short circuit to ground in the engine harness, sensor, or ECM.

Possible repairs:

1)Replace the engine speed sensor.
2)Replace the ECM.
3)Repair or replace the engine harness.