PACCAR PX-9 CM2350 (2013-17) Fault Code:187 PID:SID 211 SPN:3510 FMI:4 Sensor Supply 2 Circuit – Voltage Below Normal or Shorted to Low Source

Reason:
Sensor Supply 2 Circuit – Voltage Below Normal or Shorted to Low Source. Low voltage detected at the sensor supply number 2 circuit.

Effect:
Possible reduced engine performance.

Circuit Description:
The sensor supply 2 circuit of the engine control module (ECM) provides a 5 volt supply to various sensors on the engine harness. Refer to the wiring diagram for sensor supply identification.

Component Location:
Sensor Supply 2 originates in the Engine Wiring Harness portion of the ECM. It supplies 5 volts to sensors in the engine wiring harness.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the sensor supply 2 signal voltage was out of range low.

Action Taken When the Fault Code is Active:
1) The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.
2) A default value is used for all of the sensors on the sensor supply 2 circuit.

Conditions for Clearing the Fault Code:
1) To validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.
4) For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.
5) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop Talk:
Low voltage on the +5 volt supply line can be caused by a short circuit to ground in a supply line, a short circuit between a supply line and a return line, a malfunctioning sensor, or a malfunctioning ECM power supply.

Possible Causes:
1) Faulty engine harness
2) Loose connector
3) Moisture in or on the connector
4) Wire insulation damage