Mitsubishi FUEL Manual page 203

FAIL-SAFE FUNCTION REFERENCE TABLE
When the main sensor malfunctions are detected by the diagnosis function, the vehicle is controlled
by means of the pre-set control logic to maintain safe conditions for driving.
Malfunctioning item
Air flow sensor
Intake air temperature sensor
Throttle position sensor (2nd
channel)
Engine coolant temperature
sensor
Camshaft position sensor
Vehicle speed sensor
Barometric pressure sensor
Detonation sensor
Injector
Ignition coil (incorporating pow-
er transistor)
Fuel pressure sensor
Alternator FR terminal
Accelerator pedal position sen-
sor (2nd channel)
GDI -
Troubleshooting
Control contents during malfunction
1. Suspends lean burn operation.
2. Uses the throttle position sensor signal and engine speed signal (crank angle
sensor signal) to take reading of the basic injector drive time and basic ignition
timing from the pre-set mapping.
Controls as if the intake air temperature is 25_C.
1. Suspends lean burn operation.
2. Controls the throttle opening angle feedback (half as much as the opening
rate in the normal condition) by using signals from the throttle position sensor
(1st channel). However, this controlling system is not applied if the throttle
position sensor (1st channel) and throttle position sensor (2nd channel)
combination output voltage is outside 4 - 6 V.
3. Refrains from controlling the throttle opening angle feedback if the throttle
position sensor (1st channel) is also defective.
Controls as if the engine coolant temperature is 80_C. (Moreover, the control system
is working until the ignition switch is turned OFF if the sensor signal returns to normal.)
Controls maintaining the condition before determined as failure.
Fuel will be cut-off 4 seconds after a malfunction is detected. (However, only
if No. 1 cylinder TDC has never been detected after the ignition switch is turned
to the ON position)
1. Suspends lean burn operation. However, the control is cancelled as a certain
time passes by with the engine speed of 1,500 r/min or more.
2. Suspends lean burn operation during the engine idling.
Controls as if the barometric pressure is 101 kPa.
Fixes the ignition timing as that for standard petrol.
1. Suspends lean burn operation.
2. Suspends the exhaust gas recirculation.
1. Suspends lean burn operation.
2. Cuts off the fuel supply to cylinders with an abnormal ignition signal.
1. Controls as if the fuel pressure is 5 MPa. (If there is open or short circuit).
2. Turns off the fuel pump relay (If the fuel pressure is excessively high).
3. Suspends fuel injection. (when the low pressure is detected and the engine
speed is more than 3,000 r/min)
Refrains from controlling to suppress the alternator output to electrical load.
(Operated as a normal alternator)
1. Suspends lean burn operation.
2. Controls the throttle valve position by using signals from the accelerator pedal
position sensor (1st channel). (However, the control system is not applicable
if the difference from the accelerator pedal position sensor (1st channel) output
voltage is 1.0 V or higher.)
3. Suspends the electronic controlled throttle valve system if accelerator pedal
position sensor (1st channel) is also defective.
13I-9