Allison Fault Code

SPN 191 FMI 9

Trans Warning.

Variant 1

System

Not specified

Symptom

Trans Warning.

Diagnosis, fix steps & Red Seal insights

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Variant 2

System

Transmission

Symptom

Trans is in "Limp" (3rd Gear).

Diagnosis, fix steps & Red Seal insights

The step-by-step diagnostic logic, repair actions, and field-tested insights for this code are available inside AM Fleet Integrity. Create a free account to unlock the full fault-code library.

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