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P0684

Overview

Code

P0684

Code Type

P

Code Class

P0

System

Engine

Severity Level

High

Emissions Related

true

Drivability Impact

Major

Diagnostic Protocol

OBD2

Freeze Frame Useful

true

Code Definition

Diagnostic trouble code P0684 indicates a malfunction in the engine control module (ECM) control circuit

Symptoms

Rough idle Check Engine Light

Overview applies to this diagnostic code.

Affected Systems

On This Page

  • Code Definition

  • Symptoms

  • Affected Systems

  • Possible Causes

  • Diagnostic Steps

  • Drive Safety Notes​

More Resources

Engine Control Module (ECM)

Possible Causes

Faulty ECM control circuit Wiring issues

Diagnostic Steps

1 Inspect ECM control wiring 2 Test ECM functionality

Drive Safety Notes

Faulty ECM control may lead to poor engine performance or stalling

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