Citroën C2 C3 Airbag Unit 9658316580 654583

Description

Airbag unit for CITROEN C2, C3 and pluriel cars

Part description

This airbag unit (SRS) is used to evaluate crash signals and control the activation of airbags and related safety features. Suitable as a replacement in the event of a failure of the original airbag control unit, typically when the problem in the SRS system cannot be eliminated by replacing the sensors or repairing the wiring.

For a used unit, it is crucial that the designation and product number match – mechanics most often look for it by the numbers listed below.

Technical information

• Manufacturer: Stellantis (Citroën/Peugeot)
• Model: Citroën C2, Citroën C3, Citroën C3 Pluriel
• Other numbers: 654584, 654691

Product codes

• Product codes: 9658316580, 654583

Installation recommendations

Generally/typically the installation of the airbag unit requires increased caution and adherence to safety principles. The exact procedure may vary depending on the specific design of the car.

1) Before assembly

• Compare with the old part: all product numbers (especially 9658316580 and 654583) and match other markings.
• Check the condition of the connectors (pins must not be bent, squeezed, corroded) and the body of the unit (no cracks, deformations, traces of moisture).
• If the car has been in an accident, first check the condition of the related parts of the SRS (wiring, connectors, possibly sensors) – a faulty peripheral element may cause the fault to be reported again.

2) Necessary tools and materials

• Basic set of hand tools (ratchet/bits, screwdrivers)
• Tools for safe disconnection of connectors (e.g. plastic crowbar)
• Diagnostics for PSA (for error checking after assembly)
• Cleaning agent for electrical contacts (as needed)

3) Step-by-step assembly procedure

1. Turn off the ignition and remove the key / turn off the vehicle system.
2. Disconnect the battery and allow a reasonable amount of time for the SRS to safely deactivate (according to the manufacturer’s procedure).
3. Ensure access to the unit (procedure according to the specific design of the car).
4. Disconnect the unit connectors carefully – do not pull on the wiring, release the connector locks.
5. Dismantle the unit mount and remove the original part.
6. Compare once again the numbers and connectors of the old vs. new units.
7. Mount the unit in its original location and secure with the original fasteners.
8. Connect the connectors and check that they are properly engaged and secured with fuses.
9. Check that the wiring is not stretched, not pinched and the connectors fit without tension.
10. Connect the battery.
11. Perform a diagnostic check of the SRS system and verify the fault condition.
12. Check the lights on the instrument panel according to normal behavior after starting.
• 4) Post-assembly checks and test drive/function verification
  • On diagnostics, check whether active faults in the airbag system return.
  • Verify that the SRS warning light behaves normally (if it is on, solve the problem with diagnostics – do not delay).
  • After a short drive, check again for new errors.

  5) The most common assembly mistakes + how to avoid them

  • Battery not disconnected before handling SRS: always disconnect and follow safety procedure.
  • Damage to the connectors during disassembly: release the connector fuses in the right direction, do not force them.
  • Unit replacement according to “similarity”: the matching of product numbers and markings is always decisive.
  • Ignoring the cause of the original fault: if the problem is in the cabling or peripherals, replacing the unit itself may not help.

  Reasons why the part is damaged

  • Activation of the system in the event of an accident/crash and subsequent internal blocking or saving of crash data (depending on design).
  • Damage to cabling or connectors (transitional resistors, line break, poor contact).
  • Moisture in the interior and corrosion of contacts.
  • Incompetent interventions in the electrical installation (bad connections, short circuits, incorrect handling of the SRS).
  • Voltage fluctuations when the battery is weak or when the battery is disconnected/connected improperly.