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
- Key not programmed to the car, or someone else's/wrong key is being used
- Weak transponder signal (e.g., metal or other tags nearby)
- Faulty antenna or amplifier at the ignition switch
- Fault in the immobilizer system circuit
What you can do yourself
- Make sure you're using the original programmed key
- Move other tags/keys and metal objects away from the key
- Try the spare programmed key
- If the key is new — have it programmed by a technician/dealer; if it happens again — diagnostics
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.
Source: tat.net.au
On Oleg’s website:Car computer diagnostics ↗
The explanation comes from the error code reference in the AvtoElektrik PRO app.