A fault code doesn’t yet mean the unit or sensor itself is faulty: often it’s the plug and connector leading to it.
Possible causes
- Sensor
- O2 sensor wiring or connector
- ECU (rarely)
What you can do yourself
- Check the O2 sensor connector: it often corrodes or melts from the heat of the exhaust pipe.
- This is a five-wire (wideband) sensor: it is checked with a scanner or an engine analyser — a multimeter won’t tell you much here.
OOleg’s tip: check the connector
Often the cause is simple — there is no contact in the connector (plug). Look at the connector from the back: remove the rubber seal and you will see whether a wire is corroded or has come off completely. Corrosion shows up as green deposits. Ideally, gently pull each wire towards you one at a time: a sound wire stays in place, while a corroded one simply comes off — it needs to be repaired.
Unplug and inspect connectors with the ignition off.
Find the part on Kaspi ShopBefore buying, check the part number or match the part by VIN in the Kaspi “Garage”.
Bank 1 is the side of the engine with cylinder 1. An inline engine only has bank 1.
The explanation comes from the error code reference in the AvtoElektrik PRO app.