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
- Pump relay or fuse
- Pump relay wiring
- ECU (rarely)
What you can do yourself
- Check the secondary air pump relay and fuse — see the repair manual for where they are.
- If the relay sticks, the pump runs all the time and can burn out.
- It barely affects driving, but while warming up the exhaust is dirtier and the catalyst takes longer to heat up.
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”.
The explanation comes from the error code reference in the AvtoElektrik PRO app.