VOLVO
ECM-2B1A - Rear lambda probe ageing, bank 2. Signal too high. Intermittent fault
System
Engine Control Module (ECM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
1 modelS80 (1999–2006)
Show models by year and engine (2)
What does this fault code mean?
The rear oxygen sensor on bank 2 has aged and gives a signal that is too high. The fault is intermittent, meaning it comes and goes: it has been present, but is not necessarily present right now.
Possible causes
- Leakage in the exhaust system
- Defective oxygen sensor
What you can do
- 1Read and note the code, clear it and road test to see whether it returns
- 2Inspect the exhaust system for leaks, for example by listening for a leak sound while the engine runs
- 3Check the connector at the oxygen sensor for play, contact resistance and oxidation
- 4If any leak is fixed or none is found but the fault remains, have a workshop check the sensor
Symptoms you may notice1
- The malfunction indicator lamp (MIL) comes on
What the fault can affect2
- Control using two oxygen sensors is switched off
- Diagnosis of the catalytic converter is switched off
General guidance for car owners. Diagnosis on the car can point to a different cause.