Diagnostic Trouble Code (DTC) Information ECM-2120

Condition 

This diagnostic trouble code (DTC) is stored if the engine control module (ECM) registers a short-circuit to ground or supply voltage in the signal cable for the front heated oxygen sensor (HO2S) or if there is an open-circuit.

The diagnostic trouble code (DTC) can be diagnosed when the ignition is switched on.

Substitute Value 

• Fuel trim switched off.

Possible Source 

Signal too high 

• Short-circuit to supply voltage in the signal cable
• Short-circuit to ground in the signal cable
• Damaged front heated oxygen sensor (HO2S).

Signal too low 

• Open-circuit in the signal cable
• Damaged front heated oxygen sensor (HO2S).

Fault symptom[s] 

• Malfunction indicator lamp (MIL) lit.