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Diesel particulate filter (DPF)

P2001 AdBlue (SCR) system: efficiency too low (bank 2)

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P2001 means: AdBlue (SCR) system: efficiency too low (bank 2). The AdBlue (SCR) system sprays a urea solution into the exhaust to reduce nitrogen oxides. Drive gently and have the car checked soon. The repair usually costs about €100–1500 in Estonia. The most common cause: adBlue low or poor quality.

Is it safe to drive?Get it checked soonDrive gently and have the car checked soon.
Typical repair cost€100–1500parts and labour in Estonia

What it means

The AdBlue (SCR) system sprays a urea solution into the exhaust to reduce nitrogen oxides. The computer found a fault in the AdBlue quantity, quality, pump, injector or NOx sensor. Bank 2 is the side of a V engine without cylinder 1.

What you may notice

  • AdBlue warning on the dashboard
  • A countdown of km left before the car won't restart
  • Engine light on

What could be wrong

  1. 1AdBlue low or poor quality
  2. 2AdBlue injector blocked by crystals
  3. 3Faulty AdBlue pump or heater
  4. 4Faulty NOx sensor

Repair difficulty: Moderate

What you can check yourself

Check the AdBlue level and only fill with certified AdBlue. Don't ignore the warning: eventually the car won't start. You can check the simple things yourself, but the repair is best done in a workshop.

How we fix it

  1. We check AdBlue quality and quantity
  2. We test the pump, injector and heater
  3. We check the NOx sensors
  4. We replace the faulty part

Standard SAE description: NOx Adsorber Efficiency Below Threshold Bank 2

This code usually comes with: Diesel particulate filter (DPF) lightSee what the light means →

Want a definite answer?

Bring the car to our workshop in Estonia for diagnostics. We read the fault codes, test the sensors and tell you what is wrong. Repair price depends on the work involved, generally €45 per hour.

Book a diagnostic check

Questions

What does fault code P2001 mean?

AdBlue (SCR) system: efficiency too low (bank 2). The AdBlue (SCR) system sprays a urea solution into the exhaust to reduce nitrogen oxides. The computer found a fault in the AdBlue quantity, quality, pump, injector or NOx sensor. Bank 2 is the side of a V engine without cylinder 1.

Can I drive with code P2001?

Drive gently and have the car checked soon.

How much does it cost to fix P2001?

Roughly €100–1500 in Estonia. The price depends on exactly what has failed and on the car.

How is P2001 fixed?

We check AdBlue quality and quantity. We test the pump, injector and heater. We check the NOx sensors. We replace the faulty part.

Related codes

P2002Particulate filter not cleaning properlyP2003Diesel particulate filter (DPF): efficiency too low (bank 2)P0475Exhaust pressure control valve: fault ("A")P0476Exhaust pressure control valve: reading or operation not right ("A")P0477Exhaust pressure control valve: signal or voltage too low ("A")P0402Too much gas flowing through the EGR valveP0033Turbo bypass valve: circuit fault

Based on AI combined with our hands-on workshop experience and knowledge. This information is general and prices are approximate (Estonian workshop rates). The same code can mean different things on different cars. Only an inspection of the car gives a definite answer.

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