AI Diesel Tech

Fault Code Reference

SPN 1210 FMI 1Turbo/AirMedium

Exhaust Gas Pressure — Low

Scan Tool — in guided session

DVOM Testing — in guided session

Connector Pinout — in guided session

DieselVision™ Upload photos — DieselVision™ reads diagrams, connectors, and screens with precision.

Overview

Fault Code

SPN 1210 / FMI 1

Category

Turbo/Air

Fault Type

sensor

FMI Category

performance

Severity

Medium

Derate Risk

No

Regen Inhibit

No

Inducement Risk

No

Component Location: Exhaust gas pressure sensor — on exhaust manifold

Common Symptoms

  • Exhaust back pressure low
  • Exhaust leak possible
  • Turbo performance affected

Root Causes

  • Exhaust leak upstream of sensor
  • Sensor failed
  • Exhaust system modification

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

AI walks you through every test — one step at a time. Plans start at $12.95/mo.

Derate Behavior

Power Derate

No

Mileage / Regen Notes

Exhaust leaks common at 200k–400k miles.

System Interactions

SPN 1210 FMI 1 interacts with the following systems and may trigger cascading faults if not resolved promptly.

TSB Reference: Cummins TSB 4021592 — Exhaust Gas Pressure Low Diagnosis

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.

OEM Notes

Cummins

X15: Check for exhaust leaks at manifold gaskets.

Detroit

DD15: Check exhaust flex joint for leaks.

PACCAR

MX-13: Check exhaust manifold bolts for looseness.

Deep-dive diagnostic page: SPN 1210 FMI 1 — Full FSM Sequence & Repair Steps — includes wiring notes, sensor specs, and gated repair procedures.

Get weekly diesel diagnostic tips

Real-world fault code walkthroughs, wiring tips, and shop-tested fixes — free.

No spam. Unsubscribe anytime.

Get AI-Guided Diagnosis for SPN 1210 FMI 1

The diagnostic engine walks you through every physical test — step by step, on your phone, at the truck. No guessing. No wasted parts.