Operation CHARM: Car repair manuals for everyone.

DTC ECM-2120






Condition







Diagnostic trouble code (DTC) ECM-2120 is stored if the control module registers shortly after ignition that the probe control circuit is short-circuited to ground/voltage or that there is an open-circuit in the circuit.

Substitute value
Fuel trim is shut off.

Possible source

Signal too high
- short-circuit to supply voltage in the signal cable
- short-circuit to ground in signal cable
- defective heated oxygen sensor (HO2S) or sensor guide circuit.

Signal too low
- open-circuit in signal cable
- defective heated oxygen sensor (HO2S) or sensor guide circuit.

Fault symptom[s]
None.