Description
Immobilizer unit, 1x key fob with chip, engine control unit. All matched together from one vehicle. The car started, but the remote central locking did not work. Most likely the battery in the remote is bad. Comes from a Citroën C1 (2007).
This used assembly pairs the immobilizer module, one transponder key fob and the engine ECU into a single matched set taken from the donor vehicle. It is ideal for mechanics and competent DIYers who need a ready-paired unit for Citroën C1 / Peugeot 107 platforms with the 1.0 1KR petrol Euro 4 engine. Because the parts were working together on the donor car (engine started), the set reduces time spent on part matching and troubleshooting; the only reported issue was the remote not locking, most likely due to a depleted key battery.
Key Features & Function
– Immobilizer Unit: Authorizes the correct transponder key before the ECU enables fuel and ignition circuits, preventing unauthorized engine start.
– Engine Control Unit (ECU): Manages fuel injection, ignition timing and engine sensors for the 1.0 1KR Euro 4 engine.
– Key Fob With Transponder Chip: Provides remote locking/unlocking (remote may require battery replacement) and contains the immobilizer transponder that must be recognized by the immobilizer unit.
Technical Information
- Manufacturer: Stellantis (Citroën / Peugeot)
- Model: Citroën C1 / Peugeot 107 (1.0 1KR, Euro 4)
- Product Codes: 89780-0H020, 89780-0H021, 89740-0H010, 89740-0H011, 0261208702, 89661-0H022
- Additional Numbers: 6580V7, 6252P3
Fitment And Compatibility
Designed for Citroën C1 and Peugeot 107 models equipped with the 1.0 1KR petrol engine (Euro 4). Originates from a 2007 Citroën C1. Ensure the listed product and additional numbers match the part you require before installation.
Installation And Coding – Important
– The unit is used and is “paired” with the original vehicle (VIN/PIN/keys).
– Activation options:
1) Cloning data from the old unit (EEPROM/Flash) – after cloning the unit is plug and play.
2) Virginization and subsequent initialization/telecoding via DiagBox (or online) + key adaptation.
– Recommended to be performed by a specialist with PSA service equipment (DiagBox/Lexia/PP2000).
– Before removal/installation always disconnect the battery and follow the manufacturer’s procedure to avoid damaging the unit.
Recommended Installation Notes
- Disconnect the negative battery terminal before starting work to prevent short circuits and protect electronic modules.
- Handle the ECU and immobilizer with anti-static precautions and avoid exposing connectors to moisture or dirt.
- Label connectors and routing during disassembly to ensure correct reconnection; secure connectors fully and avoid bent pins.
- After fitting, follow the coding/initialization route described above to ensure keys and immobilizer are properly synchronized with the ECU.
Typical Failure Causes
The most common reasons these systems fail or show symptoms are:
- Depleted Key Fob Battery: Remote locking/unlocking failure is often simply a flat battery in the key fob.
- Immobilizer Synchronization Loss: Electrical faults, battery disconnection or module replacement can desynchronize keys and immobilizer.
- Water Ingress / Corrosion: Moisture or corroded connectors can cause intermittent faults or permanent damage to modules.
- Electrical Surges / Starter Motor Issues: Voltage spikes or poor grounding can damage ECU electronics.
- Internal Module Fault: Capacitor failure or solder joint problems inside the ECU/immobilizer can lead to non-start conditions.
Why Choose This Set
This matched set saves time for workshops and experienced DIYers by delivering components already working together on the donor vehicle. Ideal when the engine runs but remote locking or key recognition is unreliable — often the fastest path back to a properly operating vehicle when combined with correct coding or cloning procedures.
What Is Included
- Immobilizer Unit
- Engine Control Unit (ECU)
- One Key Fob With Transponder Chip
Notes
Remote control issues are commonly resolved by replacing the key fob battery first. For full functionality (start authorization and remote features) follow the installation and coding instructions above. Use appropriate PSA diagnostic equipment for programming or cloning to ensure reliable operation.
