On-Board Diagnostic System

Note: If trouble with any major sensor is detected by the on-board diagnostic system, the ECM will use the following set of defaults.

Volume Air Flow Sensor Fault
1. The injector's basic drive timing and basic ignition timing are read in from the preset map using the throttle position sensor (TPS) signal and engine revolution speed signal (crankshaft position sensor signal).

2. The idle air control motor is fixed at the specified position, and the idle revolution speed control is not executed.

Intake Air Temperature Sensor Fault
The control is executed with the suction air temperature regarded as 25°C (77°F).

Throttle Position Sensor (TPS) Fault
The fuel injection rate is not increased for acceleration according to the throttle position sensor signal.

Coolant Temperature Sensor Fault
The control is executed with the coolant temperature regarded as 80°C (176°F). (Even if the sensor signal becomes normal again, the control is continued until the ignition switch is turned off.)

Camshaft Position Sensor Fault
1. Simultaneous injection of fuel is executed for all cylinders. (In this case, the No.1 cylinder top dead center is not detected at all after the ignition key is turned on.)

2. Fuel is cut 4 seconds after trouble is detected. (In this case, the # 1 cylinder top dead center is not detected at all after the ignition key is turned ON.)

Barometric Pressure Sensor Fault
The control is executed with the pressure regarded as 101 kPa (760 mmHg, 14.7 psi).

Knock Sensor Fault
Change the ignition timing from the timing for premium gasoline to the timing for regular gasoline--retarded from premium setting.

Ignition Coil and Power Transistor Fault
Fuel is cut in the cylinder where the ignition signal is abnormal.

Oxygen Sensor Fault
Closed loop control of the air/fuel mixture ratio is not executed.