Circuit DescriptionBetween each injection event, the Electronic Control Module (ECM) attempts to recharge the injector power supply. The injector power supply consists of a bank of capacitors; if this power supply is maintained at high voltage. Recharging is accomplished by recovering energy stored in the injector solenoids. For the injector power supply to remain fully charged, there must be good ECM battery power and ground, a good engine speed sensor, and good injector circuits.

Component LocationThe injector power supply is located inside the ECM.

Conditions for Running the DiagnosticsThis diagnostic runs continuously after key ON.

Conditions for Setting the Fault CodesThe ECM detects that the measured injector power supply voltage is lower than the commanded injector power supply voltage.

Action Taken When the Fault Code is ActiveThe ECM illuminates the RED CHECK ENGINE light and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.Conditions for Clearing the Fault CodeTo validate the repair, start the engine and let it idle for 1 minute.The fault code status displayed by INSITE? electronic service tool will change to INACTIVE immediately after the measured injector power supply voltage reaches the commanded injector power supply voltage and the diagnostic runs and passes.The ECM will turn off the amber CHECK ENGINE lamp after the diagnostic runs and passes.For On-Board Diagnostic (OBD) engines, the ECM will turn off the MIL after three consecutive trips where the diagnostic runs and passes.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 TalkThis fault code will become active after key ON if the battery charge is above a minimum threshold, and, at the same time, the measured injector power supply voltage is lower than the commanded injector power supply voltage.

Possible Cause:1) ECM failure2) ECM power Supply Harness, fuses, or Fuses holder failure3) Battery Terminal Connections4) Battery Voltage, or Battery failure5) ECM calibration