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ISB/ISBe Series Engines – FAULT CODE 343

Electronic Control Module (ECM)


Overview

CODE REASON EFFECT
Fault Code: 343
PID: S254
SPN: 629
FMI: 12
LAMP: Yellow
SRT: 

Internal ECM error.

Possibly none on performance or severe derate.
Electronic Control Module
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Circuit Description

The ECM monitors both signal voltage output to the injectors and ECM input from the engine sensors.

Component Location

The ECM is bolted to the intake side of the cylinder block near the front of the engine.

Shop Talk

  • Loose engine or chassis ground connections can cause Fault Code 343 to be logged, as well as complaints of an intermittent stumble. Pay special attention to the negative (-) starter post connection.
  • Moisture in the ECM connectors can also cause the ECM to log Fault Code 343.

Refer to Troubleshooting Fault Code t05-343

Last Modified:  26-Oct-2010
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