SPN 111 — Coolant level low

SPN 111 is the parameter the ECM is flagging on International, CAT, Detroit, PACCAR, MERCEDES, Volvo, Mack, Cummins engines. The FMI that comes with it tells you how it failed. Each failure mode below has its own causes and its own test order — do not treat them as the same repair.

FMI 1 · Data valid but below normal operating range — most severe level

Coolant level low

The reading is real and it is dangerously low. Low oil pressure, low coolant level and low rail pressure land here. Treat it as a real condition until proven otherwise.

Full diagnosis for SPN 111 FMI 1 What FMI 1 means

FMI 1 · Data valid but below normal operating range — most severe level

Engine coolant level below normal - most severe

The reading is real and it is dangerously low. Low oil pressure, low coolant level and low rail pressure land here. Treat it as a real condition until proven otherwise.

Full diagnosis for SPN 111 FMI 1 What FMI 1 means

FMI 1 · Data valid but below normal operating range — most severe level

Engine coolant level below normal - most severe

The reading is real and it is dangerously low. Low oil pressure, low coolant level and low rail pressure land here. Treat it as a real condition until proven otherwise.

Full diagnosis for SPN 111 FMI 1 What FMI 1 means

FMI 1 · Data valid but below normal operating range — most severe level

Engine coolant level below normal - most severe

The reading is real and it is dangerously low. Low oil pressure, low coolant level and low rail pressure land here. Treat it as a real condition until proven otherwise.

Full diagnosis for SPN 111 FMI 1 What FMI 1 means

FMI 1 · Data valid but below normal operating range — most severe level

Engine coolant level below normal - most severe

The reading is real and it is dangerously low. Low oil pressure, low coolant level and low rail pressure land here. Treat it as a real condition until proven otherwise.

Full diagnosis for SPN 111 FMI 1 What FMI 1 means

FMI 1 · Data valid but below normal operating range — most severe level

Engine coolant level below normal - most severe

The reading is real and it is dangerously low. Low oil pressure, low coolant level and low rail pressure land here. Treat it as a real condition until proven otherwise.

Full diagnosis for SPN 111 FMI 1 What FMI 1 means

FMI 1 · Data valid but below normal operating range — most severe level

Engine coolant level below normal - most severe

The reading is real and it is dangerously low. Low oil pressure, low coolant level and low rail pressure land here. Treat it as a real condition until proven otherwise.

Full diagnosis for SPN 111 FMI 1 What FMI 1 means

FMI 1 · Data valid but below normal operating range — most severe level

Engine coolant level below normal - most severe

The reading is real and it is dangerously low. Low oil pressure, low coolant level and low rail pressure land here. Treat it as a real condition until proven otherwise.

Full diagnosis for SPN 111 FMI 1 What FMI 1 means

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