Diagnostic Trouble Codes – FICM Codes P0611, P1378, P1379


P0611 – Fuel Injection Control Module (FICM) Performance

P1378 – FICM Voltage Low

P1379 – FICM Voltage High

The FICM requires a 12-volt power source. The FICM receives power from the vehicle batteries through the FICM relay contacts each time the key is turned to the ON position. As the key is turned to the ON position, the FICM provides an internal ground to the coil side of the FICM relay. This closes the relay contacts and provides the FICM with the necessary power. The FICM is what controls the injectors and supplies the high-voltage current that operates the injectors. The FICM is fed 12 volts and turns it into 48 volts, so low voltage can be detrimental to the module.

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