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
- Faulty certification unit (smart key) or body control unit
- Faulty immobilizer code unit (ID-box) or steering lock unit
- Smart key system wiring and connectors
- Bus communication failure between the key authentication units
What you can do yourself
- Inspect the smart key system connectors and wiring
- Try the spare programmed key
- If the wiring is OK but the fault persists — see an auto electrician for 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: obdadvisor.com
On Oleg’s website:Car computer diagnostics ↗
The explanation comes from the error code reference in the AvtoElektrik PRO app.