← All fault codes

SPN 641 / FMI 7

VGT Turbocharger Actuator — Not Responding

High
SAE J1939 turbo SPN 641 FMI 7
What it means

Variable-geometry turbo actuator not responding to commands — sticking vanes or actuator.

Seeing SPN 641 / FMI 7?

Run a free AI diagnosis for your engine — causes ranked by real-world fix rates, with TSBs and parts.

Run a free diagnosis
Related codes
SPN 102 / FMI 2

Intake Manifold (Boost) Pressure — Data Erratic

turboMedium
P0234

Turbocharger Overboost Condition

turboHigh
P0299

Turbocharger Underboost Condition

turboHigh
P2262

Turbo Boost Pressure Not Detected — Mechanical

turboHigh

General reference only — always confirm against the OEM procedure for your specific engine.