Kit réparation Dynaparts pour système ADBLUE HDI PSA U029E ou P20E8

On many PSA Group vehicles equipped with the AdBlue (SCR) emissions control system, a recurring problem leaves owners stranded: the temperature sensor integrated into the AdBlue tank malfunctions. The engine control unit (ECU) detects an inconsistent value or a lack of signal and displays the fault codes P20E8 (reducer quality malfunction) and/or U029E (loss of communication with the AdBlue module). As a result, the vehicle enters limp mode, a countdown timer begins, and without intervention, the engine eventually stalls.

The cause is almost always the same: the original temperature sensor, in constant contact with urea (a corrosive liquid), gradually degrades.

The cable, connections, and sensor body are damaged, causing a drift out of tolerance or a complete signal loss.

Before taking action — check with an ohmmeter:

The PSA AdBlue temperature sensor is an NTC thermistor (resistance that decreases as the temperature rises). To confirm that it is indeed the cause of the fault before any intervention, disconnect the connector on the tank side and measure the resistance between the two yellow wires with an ohmmeter (20 kΩ range). At room temperature (~20°C), a sensor in good condition should read approximately 10,000 Ω (10 kΩ). Faults observed in the workshop result in aberrant values: less than 1,000 Ω (sensor drifted or short-circuited) or infinite/out of range (open circuit — sensor broken). A value of 280 to 300 Ω at room temperature indicates a permanently faulty sensor. If Diagbox constantly displays 0°C in the tank while the outside temperature is above freezing, the sensor is almost certainly defective. This kit contains everything needed for a reliable and long-lasting repair: Stainless steel temperature sensor — body made entirely of stainless steel, resistant to urea corrosion. Tolerance range equivalent to the original part for readings perfectly compliant with the ECU requirements. Urea-resistant cable — the protective sheath resists the chemical action of AdBlue, ensuring the long-term durability of the replacement. 2 waterproof connectors — for the sensor's two electrical wires. Waterproof, to prevent any urea or moisture infiltration that could recreate the fault.

• 4 cable ties — to hold and secure the cable neatly in the engine compartment.

The procedure requires removing the AdBlue tank, then opening its removable section to access the sensor wiring. The original sensor remains in place and is not removed from the tank. Simply cut its wires as close as possible, then connect the new sensor to the existing wiring harness using the supplied waterproof connectors. Clearing the fault codes with a diagnostic tool completes the procedure.

Vehicles mainly concerned: 1.6 BlueHDi (DV6) and 2.0 BlueHDi (DW10) Euro 6.1 produced up to November 30, 2019, as well as the 1.5 (DV5), 2.0 (DW10) and 2.2 BlueHDi (DW12) Euro 6.2 manufactured up to December 31, 2022.