Do it yourself
Frequently asked questions about cars and motorcycles
Car tutorial (Do it yourself) Motorcycle tutorial (Do it yourself) Frequently Asked Questions

A very common problem with the Mercedes Citan 1.5 dCi.

Model: Mercedes Citan W420 - Years: 2021, 2022, 2023, 2024, 2025, 2026
Part: Checks and maintenance

See other generations:
Video tutorial

A very common problem on the Mercedes Citan 1.5 dCi is the breakage of the differential pressure tube, which connects the DPF to the pressure sensor. The tube is often made of rigid plastic, or rubber not resistant enough to heat; moreover, it is located in a very crowded engine compartment and subject to vibrations, high temperatures, and mechanical stresses.

If this tube breaks or comes loose, the pressure sensor no longer correctly reads the pressure difference between the inlet and outlet of the DPF, so the ECU receives incorrect information. As a result, the yellow engine light comes on; an error message on the display "start engine to regenerate particulate filter" (even if not needed); emergency mode can be activated, with a reduction in engine power.

The errors that can be read with an OBD tool are P2452 (loss in the differential pressure sensor circuit) and P2453 (sensor signal out of range). For the repair, there are metal repair kits available (AliExpress code 1005007508965535 priced at 22.74 euros, free delivery).


Posted on 13 September 2025 by ScegliAuto


Related tutorials

How to Reset the Service Light on a 2021 Mercedes Citan
How to Reset the Service Light on a 2021 Mercedes Citan
Mercedes Citan (2021-2026 / W420) If you own a Mercedes Citan and don't know how to reset the service light on the instrument panel, you can refer to the video available here and reso…
How to Reset the "Service" Light on a Mercedes Citan
How to Reset the "Service" Light on a Mercedes Citan
Mercedes Citan (2012-2020 / MK 1) This procedure must be performed after the service has been completed. Before you start, activate the instrument cluster of your Mercedes Citan by tu…
Where is the OBD Port on the Mercedes Citan?
Where is the OBD Port on the Mercedes Citan?
Mercedes Citan (2012-2020 / MK 1) If you are having trouble locating the OBD port inside your first-generation Mercedes Citan, do not worry as the following description outlines all t…

How to open the bonnet on a Volkswagen Golf?

In this tutorial, you will see how to open the bonnet on a Volkswagen Golf MK4. This is a very simple operation that follows the standard procedure. First, open the driver's door, then locate the lever in the lower left area and pull it. Next, move to the front of the vehicle, lift the bonnet slightly, and find the second lever located just above the Volkswagen logo. At this point, simply pull it towards you, fully open the bonnet, and secure it with the prop rod. To close it, gently push it down.

Watch the video!


by ScegliAuto

More videos