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EGR valve

P0406 EGR valve position sensor signal too high

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P0406 means: EGR valve position sensor signal too high. The engine computer can't control the EGR valve properly, or doesn't trust its position sensor. OK to drive, but have it checked soon. The most common repair costs about €90–180 in Estonia, depending on make and model.

Is it safe to drive?OK to driveOK to drive, but have it checked soon.
Valve replacement€90–180parts and labour in Estonia, depending on make and model

What it means

The engine computer can't control the EGR valve properly, or doesn't trust its position sensor. The sensor voltage is too high. Usually a wire is shorted or the sensor has failed.

What could be wrong

  1. 1Valve clogged with soot · Valve replacement €90–180
  2. 2Valve connector or wire · Wiring or connector repair €45–90
  3. 3Valve motor or position sensor has failed · Sensor replacement €80–160

What you can check yourself

Check the EGR valve connector. The valve is near the intake manifold. You can check the simple things yourself, but the repair is best done in a workshop.

How we fix it

  1. We measure valve control and the position sensor
  2. We clean the valve
  3. We replace the valve

Standard SAE description: EGR Sensor A Circuit High

This code usually comes with: Check engine 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.

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Questions

What does fault code P0406 mean?

EGR valve position sensor signal too high. The engine computer can't control the EGR valve properly, or doesn't trust its position sensor. The sensor voltage is too high. Usually a wire is shorted or the sensor has failed.

Can I drive with code P0406?

OK to drive, but have it checked soon.

How much does it cost to fix P0406?

It depends on the cause: valve replacement €90–180; wiring or connector repair €45–90; sensor replacement €80–160. Prices include labour at €45/h, depending on make and model.

How is P0406 fixed?

We measure valve control and the position sensor. We clean the valve. We replace the valve.

Related codes

P0405EGR valve position sensor signal too lowP0407EGR valve: signal or voltage too low ("B")P0408EGR valve: signal or voltage too high ("B")P0410Secondary air system: circuit faultP0411Secondary air pump not delivering enough airP0412Secondary air valve: circuit fault ("A")P0424Catalyst temperature sensor: too low (heated catalyst, bank 1)P0093Large leak in the fuel system

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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