2014 Audi A6 CPNB - 15474 - Particulate Matter Sensor - P24AE

[SaVAGeSoot]

I had a "lingering" code that didn't go away after the self clear counter ran out.... so I cleared it because it was annoying me.....

Friday,27,December,2024,14:18:57:38535

Mileage: 141876km
 
-------------------------------------------------------------------------------
Address 01: Engine (J623-CPNB)       Labels:. 059-907-401-V2.clb
   Part No SW: 4G0 907 401 N    HW: 4G0 907 401 E
   Component: 3.0TDI FSA    H14 0016  
   Revision: 58H14---    CVN: FC1A821BB09F27B738D3FF82755A2113C7A35307
   Coding: 0A2A4012056601050000
   Shop #: WSC 49178 001 1048576
   ASAM Dataset: EV_ECM30TDI0114G0907401N 002016
   ROD: EV_ECM30TDI0114G0907401N_002.rod
   VCID: AE592569F18142E6E1-80FA
   VINID: 9D195A7535932557800C60071868100DBC

1 Fault Found:
15474 - Particulate Matter Sensor 
          P24AE 00 [01100000] - Electrical Malfunction
          Intermittent - Not Confirmed - Tested Since Memory Clear

Readiness: 0 0 0 0 0

Now I have a MIL to annoy me instead

Sunday,05,January,2025,13:29:49:38535

Mileage: 141976km   

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
                Address 01: Engine       Labels: 059-907-401-V2.clb
Control Module Part Number: 4G0 907 401 N    HW: 4G0 907 401 E
  Component and/or Version: 3.0TDI FSA    H14 0016
           Software Coding: 0A2A4012056601050000
            Work Shop Code: WSC 49178 001 1048576
              ASAM Dataset: EV_ECM30TDI0114G0907401N 002016 (AU57)
                       ROD: EV_ECM30TDI0114G0907401N_002.rod
                      VCID: AE592569F18142E6E1-80FA
1 Fault Found:

15474 - Particulate Matter Sensor 
          P24AE 00 [11101101] - Electrical Malfunction
          MIL ON - Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Priority: 2
                    Fault Frequency: 1
                    Mileage: 141917 km
                    Date: 2024.12.31
                    Time: 12:03:07

                    Engine RPM: 888.50 /min
                    Normed load value: 50.6 %
                    Vehicle speed: 1 km/h
                    Coolant temperature: 68 蚓
                    Intake air temperature: 8 蚓
                    Ambient air pressure: 960 mbar
                    Voltage terminal 30: 14.500 V
                    Unlearning counter according OBD: 40
                    Exh u PP Ds Batt Snsr Raw: 14.5 V
                    Com i PP Ds IDE Raw: 0.000 渙
                    Exh i PP Ds IDE Shnt Circ: 0.0 渙
                    Exh st PP Ds St Ma-Bits 0-7: 2
                    Particle sensor: surface temperature: 599.85 蚓
                    Particle sensor: heat voltage: 0.00 V

 

[SaVAGeSoot]

Did a quick log... I'm not feeling the zero readouts, but they all appear to be on deceleration, so I'm not sure if that's a thing or not at this stage.

 

[SaVAGeSoot]

Apparently....

DTC	Error Message	Malfunction Criteria and Threshold Value
P24AE	PM Sensor Functional check /Shorted or Open	• Current (IDE) @ measurement1 < 2 µA • Difference between current(IDE) measurement 1 and 2 or • Signal voltage positive connection (IDE) > 4.7 [V] • Signal voltage positive connection (IDE) < 0.3 [V]

 

[Dr Sheldon]

15474 - Particulate Matter Sensor

What is a Particle Matter Sensor ??

I'm sure I have never seen or heard of one - Ever !


Where do they fit is and what is the principle of its operation / function ?

 

[SaVAGeSoot]

I'm sure I have never seen or heard of one - Ever !

I'm being Punk'd right?
Particulate Matter Sensors

 

[SaVAGeSoot]

Particulate-filter diagnosis
Diesel system
The diesel particulate filter is currently
monitored for the most part for filter
breakage, removal, or blockage. A differential-
pressure sensor is used to
measure the pressure differential (exhaust-
gas backpressure downstream
and upstream of the filter) at a specific
volumetric flow. The measured value can
be used to verify whether the filter is defective.
An extended function uses load
models to monitor the efficiency of the
particulate filter.
Since model year 2010 the regeneration
frequency has also had to be monitored.
Since model year 2013 a particulate
sensor has been used to monitor the
particulate filter in response to tightened
OBD requirements in the USA. The particulate
sensor (from Bosch) operates
according to the “collection principle”,
i.e. the soot collected over a specific distance
driven is evaluated using a model
for a threshold-value filter. If the collected
soot matter, as a function of different parameters,
exceeds a certain threshold,
the particulate filter is detected as faulty.
Combined particulate-filter faults (e.g.
broken and melted filters) can also be
detected with the particulate sensor.

 

[Dr Sheldon]

I'm being Punk'd right?
Particulate Matter Sensors

Nope

That looks like a NOx sensor to me ? Same thing ?

 

[Dr Sheldon]

Since model year 2013 a particulate

sensor has been used to monitor the

particulate filter in response to tightened

OBD requirements in the USA.

 

[Dr Sheldon]

Perhaps it is just a NAR thing ?

 

[SaVAGeSoot]

You're killing me. I strongly suggest reading said handbook.

Particulate sensor
The emission regulations in the USA and
in Europe necessitate the use of diesel
particulate filters (DPF) in diesel vehicles.
Particulate sensors in addition to the differential
pressure sensor are required to
comply with future on-board diagnosis
legislation (OBD), which places more
stringent demands on the monitoring of
the functional capability of these particulate
filters. The particulate sensors measure
the soot emissions downstream of
the particulate filter.

Design
The sensor element consists of an interdigital
structure with two comb-shaped
platinum electrodes on a ceramic substrate
with an integrated heater element,
as is familiar from the λ sensor (Figure
10). A platinum meander serves to
measure the temperature of the sensor
element.

Operating principle
The particulate sensor is a resistive sensor.
A direct voltage of for example 60 V
is applied at the interdigital structure with
initially
very high electrical resistance. As
a result of the field forces soot particles
from the exhaust gas collect on the interdigital
electrodes and form increasingly
conductive soot paths between the two
comb-shaped structures. This produces
a monotonously increasing current between
the electrodes (Figure 11). A predefined
current threshold value is reached
after a certain collection time. This triggers
regeneration, in which the initial
state is re-established when the sensor
element is heated and the soot is burned
off at temperatures above 600 °C.
The time between the start of measurement
and the start of regeneration is
defined as the trigger time. An integrated
temperature-measurement meander is
used to control the temperature to ensure
that a controlled regeneration of the sensor
element takes place.
The particulate-sensor element is, like
that of the λ sensor, installed in a sensor
housing. Because particulate deposits on
the sensor element are desired here, particular
emphasis is placed on the design
of the protective tube.

Electronics
The particulate sensor, like the NOx sensor,
is equipped with evaluation electronics.
The latter supply the sensor current
and the signal status via a CAN bus.
A microcontroller
controls the timing of
measurement and regeneration and the
compensation of data in response to the
measured sensor-element temperature.
The electronics also include a voltage stabilizer,
a CAN driver, and the output stage
for the heater element.

Etc..... etc... etc....

 

[Dr Sheldon]

Book you've never heard of

Bosch Automotive Handbook by chance ?

 

[SaVAGeSoot]

Correct, as per post #6

 

[Dr Sheldon]

You got me doubting myself here ..........

I am sure we do not have them here in the UK !

Never seen and heard of one !!

 

[SaVAGeSoot]

I'm not suggesting that you have them over there, but I can assure you that both my Touareg and my A6 have them on this side of the pond...

 

[Dr Sheldon]

I'm not suggesting that you have them over there, but I can assure you that both my Touareg and my A6 have them on this side of the pond

Never Mind

 

[SaVAGeSoot]

You may not even be cray cray after all....

 

[Dr Sheldon]

Lets move on

 

[Uwe]

I'm not feeling the zero readouts, but they all appear to be on deceleration, so I'm not sure if that's a thing or not at this stage.

"Decel" means no fuel is being injected, right? And that would mean no particulates are being generated, no?

-Uwe-

 

[SaVAGeSoot]

"Decel" means no fuel is being injected, right? And that would mean no particulates are being generated, no?

-Uwe-

Agree

 

[SaVAGeSoot]

Yesterday's back-and-forth with @Dr Sheldon regarding this sensor being a thing or not, has caused me to dream up the potential option of perhaps "long coding" the PM sensor out of the controller, since it appears to only be a thing on NAR vehicles..... does anyone know if this might be possible?