PSA BSI Dump Guide: Peugeot 207, 307, Citroen C4 and C3 Body Computer Replacement

The car is a 2007 Citroen C4 and it came in on a truck. The wipers had been running on their own for a week, then one morning the dash stayed dark and the starter wouldn’t turn. The garage before you had already tried a battery and the usual BSI reset (battery off, doors shut, ten minutes, back on). The label under the fusebox lid reads 9654425680, Johnson Controls, and the owner wants a price. That’s a BSI job, and it comes down to what is inside the dump and how you move it across.

What lives inside a PSA BSI dump

The BSI is the body computer on Peugeot and Citroen from the late 1990s up to the BSI2010 and later platforms. Its memory holds more than lighting and wiper logic:

• The VIN and the vehicle configuration (telecoding: engine type, gearbox, options, market).
• The immobiliser data: the transponder keys, the pairing with the engine ECU and the four-digit PIN on most versions.
• Mileage, which the BSI shares with the cluster and the engine ECU.
• Service counters and stored faults.

So when a BSI dies, a bare replacement won’t start the car. Either the new unit is virgin and gets paired and telecoded from scratch, or you carry the old data across in the dump.

Which BSI have you got

Four suppliers cover almost everything you will see in a European workshop. The supplier matters because the memory type and the way to read it change.

• Johnson Controls (JCI): 206, 307, C3, C4, Xsara Picasso, Berlingo. Our Citroen C4 dumps 9654425680 and 9661161980 are both JCI units. Serial EEPROM, straightforward on the bench.
• Siemens/Continental: 407, C5, 807, some 307 phases. Read through the microcontroller on most versions, not a separate EEPROM.
• Valeo: 1007, 207, 308, C4 Picasso, the BSI2004 and BSI2010 families. Valeo units are the ones most often drowned by water in the footwell.
• Delphi: later 208, 2008, C3 III, DS3. Internal flash on the MCU, and the newer ones are locked against simple reads.

Read the full label before you order anything. The supplier name is printed next to the PSA number, and our label guide shows where the software index sits.

Replacing a BSI with a dump: the sequence that works

1. Read the old BSI first, even if it is misbehaving. Most failures are a shorted output or a corrupted sector, and the immo area is usually intact. Use UPA, XProg or Orange5 on the EEPROM, or the MCU route on Siemens units.
2. Source a donor with the same PSA number and the same supplier. A 9654425680 is not interchangeable with a 9661161980 even on the same C4; the software index and the populated outputs differ.
3. Write the old dump into the donor. If the old dump is unreadable, use a virgin dump for that exact number and prepare to pair keys.
4. Fit it, connect Diagbox, and open the telecoding page. Compare it with the car (rain sensor, auto lights, alarm, gearbox type).
5. Test every key, then the automatic functions (one-touch windows, wiper park, fuel gauge).

Virgin BSI or cloned BSI

A cloned unit (old dump written into a matched donor) keeps the keys, the VIN and the mileage. Nothing needs pairing and the engine ECU never notices the change. That’s the way to go whenever the old dump is readable.

A virgin BSI has the immo area blank. Diagbox pairs it to the engine ECU with the PIN and learns the keys, but you need the PIN, working keys and a dealer-level session on the newer platforms. It’s the fallback when the old unit is dead, or when the customer bought a second-hand BSI that is already married to another car.

Symptoms that point at the BSI

• Wipers, indicators or horn operating by themselves.
• Central locking cycling, dash lights flickering after rain.
• No crank with the key recognised, engine ECU reporting no communication with the BSI.
• Economy mode that never clears, or a battery that drains overnight because the BSI never sleeps.
• Diagbox cannot reach the BSI at all while the engine ECU and ABS answer.

Two things that look like BSI faults and aren’t: a corroded earth under the battery tray, and water in the BSI connector on the 307 and Xsara Picasso. Check both before you start soldering.

Can I fit a BSI from a breaker without touching the dump?

Only if you accept the donor’s keys and VIN, which means no start. On BSI2004 and later, Diagbox refuses to telecode a unit whose VIN doesn’t match the engine ECU.

Does the mileage move with the dump?

Yes. If you clone, the car keeps its true mileage. If you fit a virgin unit, the BSI takes the mileage from the cluster on most versions, and the value isn’t editable afterwards.

We keep the Citroen C4 BSI dumps 9654425680 and 9661161980 and many other units in the Johnson Controls and immobilizer sections. If your number isn’t listed, send the label photo and the supplier name through the request form and say whether you need the virgin version or a full dump.