5.6.2 Monitoring Structure

Fig 1: Monitoring Structure

Courtesy of LAND ROVER NORTH AMERICA, INC.

Thermostat Monitoring

Component/System	Fault Codes	Monitoring Strategy Description	Malfunction Criteria	Threshold value	Secondary Parameter	Enable Conditions	Time Required	MIL Illumination
Thermostat stuck open	P0128	Functional check using engine coolant and radiator outlet temperature	Time after start (depends on start temperature) ECT at engine start				from > 300s at -30 °C to > 120s at > 8.3°C <60°C	50 s / once per drive cycle	two driving cycles
			Step 1 Radiator outlet temperature within window	ECT - 6.8°C < Radiator out temp < ECT + 6.8° C
			Step 2 Radiator outlet temp AND ECT	> Radiator outlet temperature at start + 30.0°C "LESS THAN EQUAL TO" 72.0°C	Total time in ORFCO Ambient temperature	< 60 s > -10°C
Coolant Temperature Sensor (Radiator Outlet)	P1118	Short to Battery positive or open circuit	Implausible reading	< - 38.3°C	If intake air temperature Then wait for	< -5.25°C 20 s after start	2.5 s / continuous	two driving cycles
	P1117	Short to ground	Implausible reading	> 138°C	If intake air temperature Then wait for	< -5.25°C 20 s after start	2.5 s / continuous
	P1113	Plausibility checks
		Short Test (at engine start)	Radiator Outlet Temperature at start - ECT at start	> 15°C	ECT at start	< 60°C	Immediately/Once per engine start
		Main Test	Maximum radiator outlet temperature- minimum radiator outlet temperature	< 2.3°C	Short test ECT Engine speed Engine operating condition	Vehicle speed	passed > 60 °C > 1000 RPM Part load >6.2 mph
-10°C followed by 240 s to confirm the fault condition/Once per engine start

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.