Group 28 Engine Control Module (ECM) Diagnostic Trouble Codes (DTCs) ECM SPN 158, Keyswitch Battery Potential – MID 128 PID 158/PSID 124 ECM SPN 171, Ambient Air Temperature – MID 128 PID 171 23 FMI 15 • Data valid but above normal operating range - Least severe level • Sensor out of range • Sensor indicates a invalid value • MIL illuminated • Faulty Sensor FMI 17 • Data valid but below normal operating range - Least severe level • Sensor out of range • Sensor indicates a invalid value • MIL illuminated • Faulty Sensor Type of fault: FMI Description: Fault Condition: Possible Symptoms: Possible Cause:
FMI 0 • Data valid but above normal operational range • Engine Control Module battery voltage too high • N/A • Charging system fault • External charger • Engine control module (ECM) FMI 1 • Data valid but below normal operational range • Engine Control Module battery voltage too low • Starter will not crank • Charging system fault • Battery • Ground connection FMI 3 • Voltage above normal, or shorted to high source • Engine Control Module battery voltage too high • N/A • Charging system fault • External charger • Engine control module (ECM) FMI 4 • Voltage below normal, or shorted to low source • Engine Control Module battery voltage too low • Starter will not crank • Charging system fault • Battery • Ground connection FMI 16 • Data valid but above normal operating range - Moderately severe level • Engine Control Module battery voltage too high • N/A • Charging system fault • External charger • Engine control module (ECM) FMI 18 • Data valid but below normal operating range - Moderately severe level • Engine Control Module battery voltage too low • Starter will not crank • Charging system fault • Battery • Ground connection Type of fault:
FMI Description: Fault Condition: Possible Symptoms: Possible Cause: FMI 2 • Data erratic, intermittent or incorrect • Key ON, Ambient Air Temperature message missing on SAE J1939 and SAE J1587 data links • N/A • Faulty instrument cluster • Faulty harness