Fail-Safe/Backup Function (Limp-In Mode)

The following is a list of the Fail Safe Trouble item, and the controls to be provided in the event of trouble occuring.

VOLUME AIR FLOW SENSOR
1. Based on throttle position sensor (TPS) signal and engine speed signal (crank angle sensor signal), basic driving time of injectors and basic ignition timing is read from the preset map.
2. Idle air control motor fixed at predetermined position, and no idling speed control achieved.

INTAKE AIR TEMPERATURE SENSOR
Controls provided on the assumption that intake air temperature is 25°C (77°F).

THROTTLE POSITION SENSOR (TPS)
No additional fuel injection provided on the basis of throttle position sensor signal at acceleration.

ENGINE COOLANT TEMPERATURE SENSOR
Controls provided on the assumption that engine coolant temperature is 80°C (176°F) (Even if the sensor signal returns to normal, this control mode is retained until the ignition switch is set to OFF.).

CAMSHAFT POSITION SENSOR
1. Fuel injected into the cylinders in the order 1-2-3-4-5-6 with irregular timing (Provided that no No. 1 cylinder top dead center has been detected since the ignition switch was placed in the ON position).
2. Fuel cut 4 seconds after a failure was detected (Provided that no No. 1 cylinder top dead center has been detected since the ignition switch was placed in the ON position).

BAROMETRIC PRESSURE SENSOR
Controls provided on the assumption that barometric pressure is 101 kPa (760 mmHg.) (sea level).

KNOCK SENSOR
Ignition timing is changed from that for premium gasoline to that for regular gasoline.

IGNITION COIL AND POWER TRANSISTOR UNIT
Fuel cut for cylinders whose ignition signal is abnormal.

COMMUNICATION LINE WITH TRANSMISSION CONTROL MODULE
No ignition timing retard control (overall engine-transmission control) achieved when transmission speeds are changed.

HEATED OXYGEN SENSOR (front)
No air/fuel ratio feedback control (closed loop control) achieved.

HEATED OXYGEN SENSOR (rear)
Only signals of oxygen sensor (front) installed upstream of catalyst are used, and the air-fuel ratio feedback control (closed loop control) is not performed.

MISFIRE DETECTION
The ECM stops supplying fuel to the cylinder with the highest misfiring rate if a misfiring that could damage the catalytic converter is detected.