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Frequently asked questions about cars and motorcycles

Troubleshooting AdBlue P20E8 and P20A2 on a Peugeot

Model: Peugeot 308 P5, MK 3 - Years 2021-2026
Part: AdBlue warning light

In this video, we see that the previous owner of this Peugeot resolved their issues with the AdBlue control unit by disconnecting the contacts: unfortunately, this is a solution that many desperate Peugeot owners adopt, but it is not the correct one. Instead, here’s how to proceed: with the P20E08 error, the only option is to replace the tank, but first, remove the control unit, check it through the electronics, and restore it to the original Peugeot factory settings, then put it back in place, and change the AdBlue tank. Next, reset the error using the EOBD tool (of course, we do this with professional equipment). The AdBlue starts to function after the catalyst reaches 200°C, so to see the problem, we need to heat the catalyst properly; otherwise, it won’t show any issues. We fully agree that the used vehicle being sold must be original, with no strange modifications made by users.

Updated on 31 August 2026 by ScegliAuto

Video tutorial

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How to Open a Stuck Boot on the Peugeot 407?

On the Peugeot 407, the boot may become stuck, possibly due to a problem with the control button or the lock actuator. In such cases, you can perform an emergency opening by following the simple procedure shown in this tutorial. First, open the rear doors, then lower the seat back by operating the release lever. Next, go inside the boot, locate the lock, and manually operate it using a flathead screwdriver. The boot will then be free to open.

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by ScegliAuto

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