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How to check the quality of AdBlue liquid in a diesel vehicle

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Here we’re looking at how to check the quality of AdBlue liquid in a diesel vehicle.

If the ECU is reporting a quality problem or fault code P025C, we need to know whether this is a sensor fault or something wrong with the liquid.

The way to test this is by using a Delphi diagnostic tool and a refractometer. What we’re looking for is exactly the right urea concentration in the liquid. 

In this video we’ll show you:

• The procedure for testing AdBlue quality
• How to use the refractometer and diagnostic tool
Diagnostics & Test Equipment Diesel Fuel Systems How to Technicians

What will happen to the vehicle if there’s something wrong with the AdBlue?

AdBlue liquid and systems have to work at 100%, otherwise it can impair the vehicle’s performance and functioning. The car can enter a degraded mode or limp mode. It can even have the car’s request to start blocked if the vehicle runs out of AdBlue.

What is the ideal urea concentration of AdBlue liquid?

The ideal concentration should be 32 or 32.5%.

How do I find the measurement using a Delphi diagnostic tool?

In the live data list, simply look for the value ‘urea concentration’


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