Claims:1. A method of predictive diagnostics in a diesel exhaust 5 system, the
diesel exhaust system comprising at least a first temperature sensor
(102) and a second temperature sensor (103) , the first temperature
sensor (102) placed upstream from the catalyst (101), the second
temperature sensor (103) placed downstream from the catalyst
10 (101) and upstream from a diesel particulate filter (DPF (105)), the
first and the second temperature sensors in communication with an
Electronic Control Unit (ECU (104)), the method comprising:
retrieving a modelled value of temperature;
receiving a second value of temperature from the second
15 temperature sensor (103);
calculating a difference between said second value and said
modelled value in dependence of a first set of inputs;
predicting a failure in the diesel exhaust system based on the
said calculation.
2. The method of predictive diagnostics in a diesel exhaust system as
claimed in claim 1, wherein the first set of inputs comprise a status
of the DPF (105), regeneration count data for the DPF (105).
3. The method of predictive diagnostics in a diesel exhaust system as
claimed in claim 1, wherein the calculation is done when the DPF
(105) status is in regeneration mode and regeneration count is
below a pre-defined threshold.
4. The method of predictive diagnostics in a diesel exhaust system as
claimed in claim 1, wherein the prediction of failure is done when
the calculated difference remains constant for a predefined duration
of time.
5. An Electronic Control Unit (ECU (104)) adapted for predictive
diagnostics in a diesel exhaust system, the diesel exhaust system
comprising at least a first temperature sensor (102) and a second
temperature sensor (103) , the first temperature sensor (102) placed
15 upstream from the catalyst (101), the second temperature sensor
(103) placed downstream from the catalyst (101) and upstream
from a diesel particulate filter (DPF (105)), the first and the second
temperature sensors in communication with the ECU (104), the
ECU (104) configured to:
20 retrieve a modelled value of temperature;
receive a second value of temperature from the second
temperature sensor (103);
calculate a difference between said second value and said
modelled value in dependence of a first set of inputs;
predict a failure in the diesel exhaust system based on the
said calculation.
6. The Electronic Control Unit (ECU (104)) adapted for predictive
diagnostics in a diesel exhaust system as claimed 5 in claim 5,
wherein the first set of inputs comprise a status of the DPF (105),
regeneration count data for the DPF (105).
7. The Electronic Control Unit (ECU (104)) adapted for predictive
diagnostics in a diesel exhaust system as claimed in claim 5, the
calculation is done when the DPF (105) status is in regeneration
mode and regeneration count is below a pre-defined threshold.
8. The Electronic Control Unit (ECU (104)) adapted for predictive
diagnostics in a diesel exhaust system as claimed in claim 5,
wherein the prediction of failure is done when the calculated
difference remains constant for a predefined duration of time. , Description:The present disclosure proposes a method (100) of predictive diagnostics
in a diesel exhaust system and an Electronic Control 5 Unit (ECU (104))
thereof. In step 201 the ECU (104) retrieves a modelled value of
temperature. In step 202, the ECU (104) receives a second value of
temperature from the second temperature sensor (103) placed downstream
of a catalyst (101). In step 203, the ECU (104) calculates a difference
10 between said second values and said modelled value in dependence of a
first set of inputs such as a status of a DPF (105), regeneration count data
for the DPF (105). In step 204 the ECU (104) predicts a failure in the
diesel exhaust system based on the said calculation. The prediction of
failure is done when the calculated difference remains constant for a
15 predefined duration of time.