The SPN 684 FMI 9 fault code is a diesel engine fault code indicating a 'Rock out mode request error.' This diagnostic trouble code suggests a communication issue between the Engine Control Module (ECM) and the Transmission Control Module (TCM), often related to electrical or software discrepancies.What SPN 684 FMI 9 MeansThis fault code represents a failure in the communication or request process
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The SPN 684 FMI 8 fault code is a diagnostic trouble code indicating a maneuver mode request error in diesel engines. This code typically involves the Engine Control Module (ECM) or Transmission Control Module (TCM) failing to process a maneuver mode request correctly. When this fault code is active, it suggests an electrical issue affecting the communication or signal interpretation between the E
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The SPN 677 FMI 7 fault code indicates an issue with the engine starter relay where the starter does not disengage. This diesel engine fault code is triggered when the Engine Control Module (ECM) detects that the starter motor remains engaged after the engine has started, which can lead to potential damage if not addressed promptly.
What SPN 677 FMI 7 Means
The SPN 677 FMI 7 fault code specifical
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The SPN 677 FMI 4 fault code is a diesel engine diagnostic trouble code indicating that the engine starter relay circuit has failed low. This means the Engine Control Module (ECM) has detected a low voltage condition in the starter relay circuit, which can prevent the engine from starting properly.What SPN 677 FMI 4 MeansThe SPN 677 FMI 4 fault code specifically refers to an electrical issue withi
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The SPN 677 FMI 3 fault code indicates an electrical issue where the engine starter relay is shorted to a high source. This diesel engine fault code suggests that the Engine Control Module (ECM) has detected an abnormal voltage condition in the starter relay circuit, which can prevent the engine from starting properly.What SPN 677 FMI 3 MeansThe SPN 677 FMI 3 fault code specifically points to a pr
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The SPN 677 FMI 2 fault code is a diesel engine diagnostic trouble code indicating an inconsistency in the starter switch signal. This code is triggered when the Engine Control Module (ECM) detects irregularities in the input from the starter switch, suggesting potential electrical issues within the starting system.
What SPN 677 FMI 2 Means
The SPN 677 FMI 2 fault code specifically points to a pr
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The SPN 667 FMI 3 fault code indicates a high voltage condition in the Starter Pin 1 18 circuit of a diesel engine. This diagnostic trouble code is triggered when the Engine Control Module (ECM) detects an unexpected high voltage signal, suggesting a potential electrical issue within the starting system.What SPN 667 FMI 3 MeansThe SPN 667 FMI 3 fault code specifically relates to the starter circui
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The SPN 656 FMI 6 fault code is a diesel engine fault code indicating an electrical issue with the injector needle control valve for cylinder #6. Specifically, it signifies that the valve circuit is shorted, which the ECM interprets as a failure in the injector's ability to properly control fuel delivery.What SPN 656 FMI 6 MeansWhen the SPN 656 FMI 6 fault code is active, it points to a short circ
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The SPN 656 FMI 5 fault code is a diesel engine diagnostic trouble code indicating an open circuit in the injector needle control valve for cylinder #6. This code suggests that the Engine Control Module (ECM) has detected a lack of electrical continuity in the circuit responsible for controlling the needle valve of the injector, which is crucial for proper fuel delivery.
What SPN 656 FMI 5 Means
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What SPN 656 FMI 4 Means
The SPN 656 FMI 4 fault code indicates an abnormal operation of the injector needle control valve for Cylinder #6 in a diesel engine. This diagnostic trouble code is triggered when the Engine Control Module (ECM) detects a minimum threshold deviation in the operation of the needle control valve, suggesting a potential issue with the fuel injection system.
Common Causes of
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