Changing the Audi A3 Exhaust Pressure Sensor

My car turned on the check engine light on my 2010 Audi A3 1.9l TDI. After scanning it with my OBD-reader, I got the following error codes:

• P0473 Exhaust Pressure Sensor 1, Signal Too High
• P2456 Diesel Particle Filter, Differential Pressure Sensor, Implausible Signal

This fix applies to my model, 2010 Audi A3 with a 1,9 liter diesel engine – but should be process should be valid on most VAG cars, Volkswagen, Audi, Skoda etc.

Video how to fix the issue:

Tools you will need

• T30 Torx screwdriver
• Pliers for the hose clamps
• VAG-COM diagnostic cable
• VCDS-software

How to change DPF Differential Pressure Sensor

1) Regenerate DPF

DPF or the Diesel Particle Filter is a filter in the exhaust system that gathers soot from the exhaust and burns it, leading to cleaner emissions.

This process helps to burn off soot from DPF and cleans the filter, making the engine breather a little easier. This part of the fix is optional, but I highly recommend it to clean the filter and make everything a bit nicer for the new sensor.

Accurate representation of the DPF regeneration:

Plug in the VAG-COM cable and open VCDS.

Enable the Particle Filter Service Regeneration:
Engine > Coding II > Enter code 21295

Drive about 20 km (12,5 miles) with your RPM between 2500 and 3500 for the regeneration to complete. Basically driving around with lower gear than usual.

You can do the regeneration few times if you have to drive around anyway.

2) Change the sensor

1. Remove heat-shield
2. Remove cable, open the lock with a flat-head screwdriver
3. Remove the T30 bolt holding down the sensor
4. Pull the hose-clamps down
5. Pull off the sensor
6. Install the new sensor, same steps in reverse order

3) Adapt the sensor and clear the MIL light

You need to adapt the sensor for it to work properly. Whole process is explained in the video above.

G450 DPF pressure Sensor adaption using VCDS

1. Turn the ignition on, engine off
2. Select Engine control module
3. Select Coding II
4. Enter code 30605 and click “Do it!“
5. Turn ignition off
6. Wait 30 seconds

Turn off the check engine light using VCDS

You need to clear fault codes from the engine control unit to turn off the MIL light.

Do not clear any codes that you haven’t actually fixed. Its recommended to save a report before clearing any codes.

1. Turn the ignition on
2. Select Engine control module
3. Select Fault Codes
4. Select Clear Codes

If your fix worked, the motor indicator light should be off and the fault code should not appear back in the fault code list. You are all done!