Description
Immobilizer Transponder Antenna for First-Generation Peugeot 107 and Citroën C1.
This Valeo immobilizer transponder antenna (part numbers 73678312 / 6160A0) is a direct-fit replacement for the transponder ring used on early Peugeot 107 and Citroën C1 models. The antenna reads the key transponder and communicates with the vehicle immobilizer system so the engine can be started. Commonly searched by its product codes, this component is a compact and inexpensive part that restores reliable key recognition and eliminates immobilizer-related no-start conditions when the fault lies within the antenna or its wiring.
Technical Information
- Manufacturer: Valeo
- Model: Peugeot 107; Citroën C1 (First-Generation)
- Product Codes: 73678312, 6160A0
- Additional Numbers: 6160A0 | 73678312
Function And Symptoms
The transponder antenna sits around the ignition barrel and detects the RFID chip inside the key when it is turned in the lock. If the antenna fails or its connector/wiring is damaged, symptoms include: immobilizer warning light or persistent flashing, engine cranks but fuel/ignition is disabled, or intermittent failures where the car starts only sometimes. In many cases technicians search by part number to confirm compatibility and source the correct replacement.
Replacement Procedure (Overview)
- Disconnect the negative battery terminal before starting work to avoid electrical damage.
- Remove lower steering column trim panels to access the ignition barrel area.
- Locate the transponder antenna ring around the ignition switch, unplug the connector and release any retaining clips.
- Swap the antenna for the new unit and reconnect the wiring. Ensure the connector is fully seated and locked.
- Reassemble trims, reconnect the battery and test with the original key(s) to verify key recognition and proper immobilizer behavior.
Installation Recommendations
- Always disconnect the battery before disassembly to prevent short circuits and potential ECU damage.
- Handle the antenna and its connector carefully — the antenna ring and its wiring are delicate and can be damaged by excessive force.
- Inspect wiring harness and connector for corrosion or broken wires; repair or replace connector clips if necessary.
- Use dielectric grease on electrical connectors to reduce the risk of future corrosion in humid environments.
- After replacement, confirm immobilizer light behavior and perform several start cycles with each key to ensure stable operation.
Why This Part Fails
- Physical Damage: Impact or improper removal of steering column trim can crack or deform the antenna ring.
- Connector/Wiring Issues: Corrosion, pin deformation or broken wires cause intermittent or permanent loss of signal.
- Moisture Ingress: Long-term exposure to moisture can corrode contacts and degrade the antenna coil.
- Electrical Disturbances: Short circuits or faults elsewhere in the ignition circuit can damage the antenna assembly.
Longevity And Notes
Transponder antennas are generally long-lived if not physically damaged or exposed to moisture. Replacement is typically only required after impact, connector failure, or when performing related steering column or ignition switch repairs. When sourcing a replacement, using the correct part numbers (73678312, 6160A0) ensures fitment for first-generation Peugeot 107 and Citroën C1 models.
