PACCAR PX-9 CM2350 (2013-17) Fault Code:3563 PID: SPN:5491 FMI:4 Aftertreatment Diesel Exhaust Fluid Line Heater Relay – Voltage Below Normal or Shorted to Low Source

Reason:
Aftertreatment Diesel Exhaust Fluid Line Heater Relay – Voltage Below Normal or Shorted to Low Source. Low signal voltage detected at the diesel exhaust fluid line heater relay.

Effect:
Possible reduced engine performance.

Circuit Description:
The aftertreatment diesel exhaust fluid line heater relay is used to provide power to the aftertreatment diesel exhaust fluid line heaters.

Component Location:
The aftertreatment diesel exhaust fluid line heater relay location is original equipment manufacturer (OEM) dependent. Refer to the OEM service manual.

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 aftertreatment diesel exhaust fluid line heater relay control signal was out or range low or open circuit.

Action Taken When the Fault Code is Active:
The ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.

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:
Reference the appropriate OEM wiring diagram when troubleshooting circuits that utilize wiring supplied by the OEM.

For intermittent power supply and datalink communication issues with Aftertreatment Components, it is highly recommended that the OEM Power Distribution Center fuses and relays be thoroughly checked for loose, missing or intermittent connections.

Possible Causes:
1) Short to ground in the aftertreatment diesel exhaust fluid line heater relay circuit
2) A short circuit to ground in the OEM harness
3) An open circuit in the OEM harness