What are common AdBlue DTCs in VW Passat?

Some of the most common AdBlue related fault codes in Passat are: P20EE00 (SCR catalyst efficiency below threshold), P20E8 (reductant pressure too low), P204F (reductant system performance), and P229F (NOx sensor 2 range/performance).

Which tools can be used to read and write the ECU file in VW Passat B7/B8?

Well-known ECU programming tools include Kess3, Kess2, KTAG, Autotuner, Flex, and PCM Flash. These tools can read and write ECU files via OBD or Bench/Boot mode depending on ECU compatibility.

Do I need to reflash the AdBlue module when removing AdBlue system?

No. In most cases, only ECM file is enough. There is no needs to reflash the AdBlue module, although some components such as NOx sensors or the AdBlue ECU (ACU) may need to be disconnected depending on the ECU type.

Where is the AdBlue tank located in VW Passat?

The AdBlue tank in the Passat B7 is typically located in the rear section of the vehicle, either in the trunk area beneath the floor near the spare wheel well or under the rear right side of the vehicle depending on the body style.

What sensors are involved in the DPF system in VW Passat B7/B8?

The DPF system uses differential pressure sensors and exhaust temperature sensors. Pressure sensors measure the difference in exhaust pressure before and after the DPF, while temperature sensors monitor exhaust temperatures upstream and downstream of the filter.

VW Passat B7/B8 AdBlue, DPF, EGR & DTC Off Guide

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VW Passat B7/B8 AdBlue, DPF, EGR & DTC Off Guide

AdBlue, DPF, EGR & DTC Delete Guide and Best ECU Tuning Tools for VW Passat B7/B8

The seventh generation of the Volkswagen Passat (B7) was produced between 2010 and 2014. It came in several variations, with our main focus being on the diesel versions equipped with the 1.6 TDI and 2.0 TDI engines. These engines use different ECUs depending on the engine code:

2.0 TDI (B7): Bosch ECUs including EDC17C46, EDC17CP54, EDC17C64, EDC17CP14
1.6 TDI (B7): Continental PCR2.1 ECU

The 1.6 TDI and some 2.0 TDI engines are Euro 5 compliant, while the 2.0 BlueTDI version uses SCR technology and meets Euro 6 standards. The eighth generation Passat (B8) was produced from 2014 to 2023. Like the B7, it features 1.6 TDI and 2.0 TDI engines, with the following ECUs:

2.0 TDI (B8): Bosch EDC17C74, MD1CP004, and EDC17CP74 (BiTDI)
1.6 TDI (B8): Bosch EDC17C74

VW Passat B7/B8 AdBlue Removal Procedure

1. Use a scanner or diagnostic tool to read and record all AdBlue-related DTCs.

Common AdBlue DTCs in VW Passat B7/B8:

P20EE00: SCR NOx Catalyst Efficiency Below Threshold
P20E8: Reductant Pressure Too Low
P204F: Reductant System Performance
P229F: NOx Sensor 2 Range/Performance (Bank 1)

2. Read the ECU file using the OBD port or Bench/Boot mode with tools such as Kess3, Kess2, K-Tag, Flex, Autotuner, PCM Flash, etc.

3. Upload the file to our website along with the related fault codes. Our experts will provide the removal solution within ~20 minutes.

4. Write the modified file back to the car using the same protocol.

5. Disconnect components depending on ECU type:

Bosch EDC17C46, EDC17CP54, EDC17C64, EDC17C74: Disconnect NOx sensors.
Bosch MD1CP004: Disconnect the AdBlue ECU and pump.

6. Clear DTCs (fault codes) using a Diagnostic tool.

Note: To remove AdBlue, DPF, or EGR, only the ECU file requires modification. The AdBlue module itself does not need to be reprogrammed.

VW Passat B7/B8 DPF Removal Procedure

For DPF removal, follow these steps:

Bosch EDC17C46, EDC17CP54, EDC17C64, MD1CP004: Disconnect DPF temperature and pressure sensors.
Bosch EDC17C74: Disconnect DPF temperature and pressure sensors.

Afterward, clear all fault codes and perform a forced regeneration cycle.

VW Passat B7/B8 AdBlue System Overview:

AdBlue Tank Location (Passat B7): Mounted at the rear of the vehicle, near the spare wheel well (in the trunk/boot area under the floor) or under the rear right side of the vehicle, depending on body type (sedan/estate).
AdBlue Module: The SCR control unit/dosing module is integrated with the AdBlue tank assembly. It contains the pump, heater, level sensor, and electronics.

VW Passat AdBlue tank, pump & AdBlue module

AdBlue tank with integrated pump and module (Passat B7)

3. NOx Sensor Locations:

Upstream NOx sensor (pre-SCR): Located in the exhaust pipe just after the turbocharger and Diesel Oxidation Catalyst (DOC), before the SCR/AdBlue injection point. It measures raw engine-out NOx to calculate required AdBlue dosing.
Downstream NOx sensor (post-SCR): Located after the SCR catalyst and DPF, toward the rear of the exhaust system. It monitors SCR efficiency and reports to the ECU.

Passat

Upstream and downstream NOx sensors on Passat exhaust

AdBlue Module-VW Passat

VW Passat B7/B8 AdBlue Module (ACU)

VW Passat B7/B8 DPF Sensor Locations:

1. DPF Pressure Sensors (Differential):

Passat B7: Usually mounted directly on the DPF housing under the car, with two hoses connected before and after the DPF.
Passat B8: Similar setup, but the sensor may be mounted closer to the engine bay and sometimes covered with heat shielding.

DPF Pressure & Temperature Sensor

DPF Pressure & Temperature Sensor

2. DPF Temperature Sensors:

Upstream: Before the DPF, monitors incoming exhaust temperature.
Downstream: After the DPF, monitors exhaust leaving the filter.

DPF & AdBlue (SCR) Diagram on Passat B7/B8

DPF & AdBlue (SCR) Diagram

Optional: Some models have a sensor inside the DPF to measure internal temperature

If you need a tested AdBlue, DPF, EGR & DTC off file for your VW Passat B7/B8, send us your ECU file and receive a professional solution in the shortest possible time.

VW Passat ECU Solution and Performance File