Diagnostic Trouble Code (DTC) Information ECM-250C: Notes

Condition 

Fig 1: Front Heated Oxygen Sensor

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The diagnostic trouble code (DTC) is stored if the engine control module (ECM) registers that the resistance in the preheating circuit for the front heated oxygen sensor (HO2S) (bank 2) is too high.

Substitute Value 

• None.

Possible Source 

• Contact resistance and oxidation in the terminals
• Damaged front heated oxygen sensor (HO2S).

Fault symptom[s] 

• Malfunction indicator lamp (MIL) lit.