VOLVO
ECM-24D0 - 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:
4 modelsC30 (2007–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
Show models by year and engine (9)
- Volvo C30 (2007–2013)2007Engine B5254T3 only
- Volvo C30 (2007–2013)2008–2013Engine B5254T7 only
- Volvo C70 (2006–2013)2006–2007Engine B5254T3 only
- Volvo C70 (2006–2013)2008–2013Engine B5254T7 only
- Volvo S40 (2004–2013)2005–2007Engine B5254T3 only
- Volvo S40 (2004–2013)2008Engine B5254T3, B5254T7 only
- Volvo S40 (2004–2013)2009–2012Engine B5254T7 only
- Volvo V50 (2004–2013)2005–2007Engine B5254T3 only
- Volvo V50 (2004–2013)2008–2012Engine B5254T7 only
What does this fault code mean?
The engine control module (ECM) watches the front oxygen sensor's signal. If the sensor reports only air and no fuel/air mixture, the code is stored, meaning the sensor is not giving a usable picture of the exhaust. The cause is then either an incorrectly fitted sensor or a damaged one.
Possible causes
- Incorrectly fitted oxygen sensor
- Damaged front oxygen sensor
What you can do
- 1Read and note the code, clear it and road test to see whether it returns
- 2Check that the oxygen sensor is correctly fitted in the exhaust system
- 3Look at the sensor connector for oxidation and loose connections. Rust solvent spray and grease must not be used
- 4Use a multimeter to check that the wiring is continuous all the way to the control module with no break
- 5If the wiring is intact but the fault remains, have a workshop try a new oxygen sensor
Symptoms you may notice1
- The malfunction indicator lamp (MIL) is 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.