Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnostic Trouble Code (DTC) Information
2004 Volvo V70 L5-2.4L VIN 64 B5244S6SECTION Diagnostic Trouble Code (DTC) Information
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 or an open-circuit in the circuit for the front probe control.
The diagnostic trouble code (DTC) can be diagnosed when the ignition is switched on.
Substitute value
- The fuel trim is shut off.
Possible source
Signal too high
- Short-circuit to supply voltage in the signal cable
- Short-circuit to ground in the signal cable
- Damaged heated oxygen sensor (HO2S) or probe control circuit.
Signal too low
- Open-circuit in the signal cable
- Damaged heated oxygen sensor (HO2S) or probe control circuit.
Fault symptom[s]
- Malfunction indicator lamp (MIL) lit.
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.