VOLVO
ECM-289A - Front heated oxygen sensor (HO2S), bank 1. Faulty signal
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
2 modelsS40 (2004–2013), V50 (2004–2013)
Show models by year and engine (2)
What does this fault code mean?
The engine control module monitors the front oxygen sensor by checking its signal. The code is stored when the sensor only indicates air and no fuel and air mixture. The sensor may be installed incorrectly in the exhaust, or it may be damaged.
Possible causes
- Oxygen sensor fitted incorrectly
- Damaged front oxygen sensor
What you can do
- 1Check that the oxygen sensor is correctly fitted in the exhaust system
- 2Check the sensor connector for contact resistance, open circuits and oxidation. Do not use rust solvent or grease in it
- 3If the fitting and connector are in order but the fault remains, have a workshop try a new oxygen sensor
Symptoms you may notice1
- Malfunction indicator lamp (MIL) lit
What the fault can affect2
- Oxygen sensor control is switched off
- Catalytic converter diagnostics are switched off
General guidance for car owners. Diagnosis on the car can point to a different cause.