Adblue System Fault - No Restart

[Animus]

Morning All,

Ive had a yellow Adblue System Fault, No Restart in xx miles flash. Its started at 650 and is now on 550. Ive ran VCDS and it didnt find a fault code however, I ran some specific tests on the reductant system and found the following:

IDE03129 Reducing agent pump: activation 50.00 %
IDE03132 Pressure sensor for reducing agent: measured pressure 4998 hPa
IDE03133 Reducing agent metering system heating circuit 1: actual current 0.0 A
IDE03135 Sensor for reducing agent tank temperature: temperature 9.6 °C
IDE03142 Remaining vehicle distance until reducing agent deficiency 870.35 km
IDE03146 Pressure sensor for reducing agent: voltage 2815.0 mV
IDE03147 Sensor for reducing agent tank temperature: voltage 1600 mV
IDE03148 Sensor for reducing agent fill level: voltage 3110.0 mV
IDE03288-ENG188621 Heating circuit 1 for reducing agent metering: activation-Bits 0-7 0
IDE03289-ENG188621 Heating circuit 2 for reducing agent metering: activation-Bits 0-7 0
IDE05232 Reducing agent fill level 98.97 %
IDE05520 Pump for reducing agent: speed 1588.0 /min

I have the following questions:

1) what should the tank temperature be?
2) What should the heating current be?
3) What should the pump activation be? (engine was at idle)
4) What further tests need to be done/actions taken to rectify the fault/whats the likely cause?

No loss of performance, just the dreaded countdown...


Best, Animus.

 

[Animus]

Update: Ive run a few more tests and ruled out the pump as that is supplying Adblue to the injector. The actual fault is:

1 Fault Found:

262659 - Control Circuit for Reductant Heating 2
P20BD 00 [008] - Open Circuit
[SCR-Leitungsheizung (Heizkreis 2)Leitungsunterbrechung]
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Reset counter: 122

Voltage terminal 30A: 12.8 V
Voltage terminal 30B: 12.8 V
Voltage terminal 87: 12.7 V
Reductant_pwm_duty_cycle: 0.0 %
Reductant_speed_pump_motor: 0 /min
Reductant_pump_output_stage_temperature: 15 C
Reductant_heater_control_1_output_stage_temperature: 15 C
Reductant_tank_temperature_sensor_actual_value: 10 C
Reductant_temperature_ambient: 77 C
Reductant_current_pump_motor_A: 0.0 A
Reductant_current_pump_motor_B: 0.0 A
Reductant_current_pump_motor_C: 0.0 A
Reductant_heater_control_1_actual_power_value: 0.0 A
Reductant_heater_control_2_actual_power_value: 0.0 A
Reductant_transfer_pump_current: 0.0 A
Reductant_pressure_sensor_actual_value: -50 mbar
Reductant_voltage_sensor_supply: 5.0 V
Reductant_voltage_sensor_gnd: 0.0 V
Reductant_level_sensor_actual_raw_voltage: 3.1 V
KL15 on: On
DIAG_Opt_H: On
Tank_L_SC: OFF
Lines_L_SC: On
DIAG_Lines_H: OFF
DIAG_Lines_L: OFF
DIAG_Tank_H: On
DIAG_Tank_L: On
MO_SCR_Dosierpumpe_Zustand: 00
MO_SCR_Tankheizung: OFF
MO_SCR_Leitungsheizung: OFF
MO_SCR_Transferpumpe: OFF
reserviert 1 0: On
Reserviert 2: OFF
Can signal MO_SCR_Dosierpumpe_Soll: 0.0 %

 

[Animus]

and some more:

14:32:56
IDE03129-ENG108430 Reducing agent pump: activation-Reductant_pump_control_commanded_value 50.00 %
IDE03132-ENG108429 Pressure sensor for reducing agent: measured pressure-Reductant_pressure_sensor_actual_value 5003 mbar
IDE03133-ENG108423 Reducing agent metering system heating circuit 1: actual current-Reductant_heater_control_1_actual_power_value 0.0 A
IDE03290-ENG114704 Reducing agent transfer pump: activation-Reductant_transfer_pump_control_commanded_value not active
IDE03585-ENG109088 System status for the start/stop function master-State_of_start/stop_functionmaster 0
IDE05520-ENG112659 Pump for reducing agent: speed-Reductant_pump_speed 1596 /min
IDE06835-ENG114706 Reducing agent pressure sensor: diag. status-Reductant_pressure_sensor_diagnostic_state No malfunction
IDE06836-ENG114707 Heating circuit 1 for red. agent metering: diag. status-Reductant_heater_control_1_diagnostic_state No malfunction
IDE06837-ENG114708 Reducing agent pump: diag. status-Reductant_pump_diagnostic_state No malfunction
IDE06838-ENG114709 Reducing agent transfer pump: diag. status-Reductant_transfer_pump_diagnostic_state No malfunction
IDE06839-ENG114710 Reducing agent fill level sensor: diag. status-Reductant_level_sensor_diagnostic_state No malfunction
IDE06840-ENG114711 Reducing agent tank temperature sensor: diag. status-Reductant_tank_temperature_sensor_diagnostic_state No malfunction

IDE03132 Pressure sensor for reducing agent: measured pressure 4998 hPa
IDE04099 Reduction agent dosing ReAg Rate/Demand:0.1/0.11 L/h / Reag Tnk Lvl:74.1 %
IDE07797 Injector 1 bank 1 for reducing agent before SCR cat: activation 0.00 %
IDE11220 Reducing agent system: current status COSCR_PRESSURECTL
IDE11221 Reducing agent system: last status COSCR_NOPRESSURECTL
IDE11222 Reducing agent system: current substatus COSCR_METERINGCONTROL
IDE11223 Reducing agent system: last substatus COSCR_PRESSUREBUILDUP
IDE11250 Reducing agent quality sensor: raw temperature value -273.1 C

Ive removed the injector and ran the engine with it out. There was no Adblue coming out of it alongside it being cold. This leans me to the injector itself being fault. Will welcome thougts.

 

[elan2s]

I had a similar problem with my 2015 A6, fortunately at the time it was under warranty and the dealer fixed it. If I recall correctly they thought it was the AdBlue pump but in the end they had to take it for a drive and after about 30miles it suddenly cleared and did not return before I changed the car.

There is an exceptionally helpful guy called Crasher on VWAudiforum.co.uk who runs his on garage specialising in VAG cars. Posting your question there may get you the information you are looking for. BTW he hates diesels and AdBlue systems because of all the issues they create for his customers, but that said there is probably no AdBlue related problem he has not come across so should be able to point you in the right direction.

 

[asalhan]

I had this issue with my 2014 A6. everything looked like it was working. I removed the injector from the DPF and it was indeed spraying adblue into the thing. mine turned out to be a seized float I think. Try topping it up to the max and see if that moves the float. I had mine booked in at a garage who then just told me to go away when I turned up with the issue - bad words were exchanged!

I ended up doing it myself on the drive with my son helping me. Apart from getting under the car, it was a pleasant and somewhat DIY-able job. I found a new tank and pump on ebay but I just ended up replacing the pump as the tank was OK. Reset all the learned values and took it for a drive, within 1/4 mile, everything was normal. Just remember to drain the tank lol