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Home >> Land Rover >> 2003 >> Freelander HSE >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> On-Board Diagnostics - Siemens Ms43 Engine Management System >> Onboard Monitoring >> 5.1 Catalyst Monitoring >> 5.1.2 Monitoring Structure
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5.1.2 Monitoring Structure

Fig 1: Monitoring Structure
G03469350Courtesy of LAND ROVER NORTH AMERICA, INC.
Catalyst Monitoring Operation

Component/System Fault Codes Monitoring Strategy Description Malfunction Criteria Threshold value Secondary Parameter Enable Conditions Time Required MIL Illumination
Catalyst 
Bank 1
Bank 2
-
P0420
P0430
Oxygen storage capability Comparison of calculated lambda-cycle to measured lambda-cycle from rear oxygen sensor
Hydrocarbon (HC) Emissions (1.75 x standard)
> 6.02 during 59 lambda controller cycles ECT
Fuel system status
Vehicle speed
Engine speed and Engine load
Engine speed
Engine load
Lambda Mean Value
Delta accelerator
pedal movement
Catalyst temperature (model)
Following Over Run Fuel Cut Off (ORFCO)
>60°C
closed loop
3.1 < vehicle speed < 124 mph
1280 to 2912 RPM
0.31 to 0.97 g/rev
"TRIANGLE" < 308 RPM
"TRIANGLE" < 0.27 g/rev
"TRIANGLE" < 4.1%
"TRIANGLE" < 504°Throttle Position Sensor (TPS)/s
399 < T °C < 899
Integrated Air Mass > 200g
90 s / once per driving cycle two driving cycles

If the above table does not include details of the following enabling conditions: - IAT, ECT, vehicle speed range, and time after engine start-up then the state of these parameters has no influence upon the execution of the monitor.