Valeo

Valeo – J34P and V34.1 engine ECUs for Peugeot and Citroën

Valeo is a French supplier of parts and systems to car manufacturers, with a history going back to the 1920s (trading as Valeo since 1980). The company makes lighting, wipers, air conditioning and cooling systems, clutches, starters and alternators, sensors and cameras for driver assistance systems, and control electronics, among other things. Its components are fitted as original equipment in cars of many brands, including vehicles of the PSA group.

At ECUSale we offer Valeo engine ECUs from the J34P and V34.1 families, used with 1.1, 1.4 and 1.6 petrol engines in many Peugeot and Citroën models.

IMMO OFF ECUs – the car starts after fitting

We prepare J34P and V34.1 ECUs as IMMO OFF. Once the ECU is fitted, the car starts without key matching and without programming with a diagnostic tool. Both families are prepared in the same way – V34.1 ECUs are also ready to fit as Plug & Play.

Examples from our range:

• 21586048-9A / 9664127180 – Valeo J34P IMMO OFF Plug & Play,
• 21586539-8A / 9665424480 – Valeo J34P IMMO OFF Plug & Play,
• V29009427A / 9675916480 – Valeo V34.1 IMMO OFF.

Symptoms of a faulty J34P or V34.1 ECU

Faults in Valeo ECUs can show up in different ways. The most common are:

• rough engine running,
• misfires,
• no signal to the injectors,
• no power supply to the ECU,
• no communication with the diagnostic tool.

Similar symptoms can also have other causes, such as a faulty coil, injector or wiring, so it is worth ruling out wiring faults before replacing the ECU.

How to choose a Valeo ECU? SW and HW numbers

The ECU label carries two PSA numbers: SW and HW (both usually starting with 96…), as well as a Valeo number (e.g. 21585… or V29…).

• SW – identifies the ECU software,
• HW – identifies the hardware version (the circuit board).

The ECU is chosen mainly by the SW number – this way the software is the same as in your current ECU. Compare the SW number on the label with the number in the product name. If you cannot see your number, send us a photo of the label and we will check which ECU fits.

Tested before dispatch

Every Valeo ECU is checked on a test bench before dispatch, so that you receive a working module ready to fit.

Frequently asked questions

Does an IMMO OFF ECU need any programming after fitting?

No. Once fitted, an IMMO OFF ECU lets you start the engine without key matching and without programming.

Are V34.1 ECUs prepared in the same way as J34P?

Yes. Both types are prepared in the same way and both are ready to fit.

Which number matters most when choosing?

The SW number, because it identifies the software. The HW number describes the circuit board. The safest choice is an ECU with the same SW number as in your car.

Which engines do Valeo J34P ECUs fit?

1.1, 1.4 and 1.6 petrol engines in various Peugeot and Citroën models. Compatibility is determined by the SW number on the label, not by the car model alone.