Failure Management

When main sensor malfunctions are detected, PCM will enter fail-safe mode. Default values will be substituted in PCM calculations for faulty sensor input as follows:

• Volume Air Flow Sensor  - PCM will use engine speed (crankshaft position sensor) and Throttle Position (TP) sensor signals to determine injector drive time and basic ignition timing. Idle Air Control (IAC) motor remains in a fixed position.
• Intake Air Temperature (IAT) Sensor  - Sets at a default of 77°F (25°C).
• Throttle Position (TP) Sensor  - Fuel injection amount will not increase during acceleration due to unreliable TP sensor signal.
• Engine Coolant Temperature (ECT) Sensor  - Sets at a default of 176°F (80°C).
• Camshaft Position (CMP) Sensor  - PCM will command injectors to inject fuel into cylinders in normal 1-3-4-2 order, but may not be synchronized with camshaft timing.
• Barometric Pressure (BARO) Sensor  - Sets at a default of 30 in. Hg (101 kPa).
• Heated Oxygen Sensor (HO2S) Front  - Closed loop fuel control is not allowed.
• Heated Oxygen Sensor (HO2S) Rear  - Allows closed loop fuel control using front HO2S signals.
• Generator FR Terminal  - Generator output suppression control of electrical load is not performed.
• Communication Line With Transaxle Control Module (TCM)  - Ignition timing retard control is inoperative when transaxle speeds change.
• Misfire Detection  - Fuel supply is stopped to cylinder if misfiring will damage catalytic converter.