Found this on TheMiniforum for an SPI
4.4.2 Component Tests on M.E.M.S Single Point Injection Vehicles
1) Engine Speed
Engine speed displayed in RPM, giving a good indication that the crank angle sensor is operating correctly. Note: If the crank angle sensor circuit is faulty the engine will not start. To diagnose a crank angle sensor fault select this test and crank the engine, a healthy sensor will show cranking RPM of around 300 RPM, a circuit fault will show no RPM reading.
2) Idle Switch
Confirms the operation of the throttle idle switch, by displaying ‘OPEN’ or ‘CLOSED’ depending on throttle pedal position. A vehicle with a faulty throttle idle switch circuit will not run correctly at idle. Note: Not fitted to 93 MV, the throttle pedal switch position Is calculated from the throttle pot position.
3) P/N Switch
Displays the state of the Park/Neutral Switch (labeled Inhibitor Switch in some manuals.) The display will show either open or closed and is only applicable to automatic vehicles.
4) MAP Sensor
Displays the output of the Manifold Absolute Pressure sensor located within the ECU itself. Nominal values approx 3OKPa at idle, approx 100 KPa with engine off.
5) Coolant Temp
Displays the output of the Coolant Sensor in °C. It should be noted that engine hot idle is not reached until the coolant temperature is above around 82°C. In ‘Limp Home’ mode the ECU sets the coolant temperature to a default value of around 60°C.
6) Inlet Air Temp
Displays the output of the Inlet Air Temperature Sensor in °C. In ‘Limp Home’ mode the ECU sets the inlet air temperature to a default value of around 35°C
7) Ambient Air
Displays the Ambient Air Temperature. (This value is calculated Temp from other engine parameters.)
8) Battery Volts
Displays the Battery Voltage as read by the ECU. If the battery voltage falls below approx 11.8 volts the ECU compensates by increasing the injection duration.
9) Throttle Pot
Displays the Throttle Potentiometer Voltage. This test is ideally performed with the engine stopped to enable the full travel of the potentiometer to be tested. A smooth increase in reading should be seen showing that no ‘Flat Spots’ are present. The range expected is approx: 0.5 to 4.0 Volts
10) Lambda Volts
Displays the output of the Exhaust Gas Oxygen Sensor (Lambda Sensor). As the sensor warms up to 300 °C the voltage can be seen switching from lean to rich. A lean reading would be about 0.1 volts and a rich reading above 1.0 volts. The lambda switching threshold is around 0.6 volts. In ‘Limp Home’ mode the ECU substitutes a reading of 0.8 volts hence running the car permanently slightly rich. Note: Lambda sensors are only fitted to vehicles with closed-loop emission control