AI Diesel Tech

Fault Code Reference

SPN 1241 FMI 8ABS

Traction Control Valve - Abnormal Frequency/Pulse Width

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DVOM Testing — in guided session

Connector Pinout — in guided session

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Overview

Fault Code

SPN 1241 / FMI 8

Category

ABS

Derate Risk

No

Regen Inhibit

No

Inducement Risk

No

Component Location: The traction control valve is typically mounted on the ABS modulator assembly or integrated into the brake system control module.

Common Symptoms

  • ABS warning lamp illuminated on dash
  • Traction control system disabled or inoperative
  • ABS fault code active with no noticeable performance change
  • Intermittent ABS warning light during vehicle operation

Root Causes

  • Faulty traction control valve solenoid Damaged wiring harness to traction control valve Corrosion or moisture in valve electrical connector Internal short or open circuit in valve coil ECU detecting improper valve pulse width modulation signal

Full step-by-step tests, DVOM guidance, and pinout data are available inside the AI Diesel Tech diagnostic session.

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Derate Behavior

Power Derate

No

System Interactions

SPN 1241 FMI 8 interacts with the following systems and may trigger cascading faults if not resolved promptly.

Common Diagnostic Mistakes

Replacing the sensor without verifying wiring continuity and supply voltage first.

Clearing codes without identifying and resolving the root cause — the fault will return.

Ignoring related active faults — cascading faults often share a root cause.

Skipping the connector inspection — corrosion and damaged pins are a leading cause of sensor faults.

Condemning the ECM before exhausting all wiring and component tests.

Deep-dive diagnostic page: SPN 1241 FMI 8 — Full FSM Sequence & Repair Steps — includes wiring notes, sensor specs, and gated repair procedures.

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