Tracker 2WD L4-1.6L VIN 6 (2000)
The PCM supplies a buffered voltage to the various information sensors and switches. The PCM monitors the input components for circuit continuity
and out-of-range values. The PCM also provides performance checking. Performance checking refers to the PCM indicating a fault when the signal from
an input does not seem reasonable (i.e. a Throttle Position (TP) sensor that indicates a high throttle position at low engine loads or low manifold absolute
pressure sensor voltage). The input components may include, but are not limited to the following sensors and switches:
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The Vehicle Speed Sensor (VSS)
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The Crankshaft Position (CKP) Sensor
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The Throttle Position (TP) Sensor
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The Engine Coolant Temperature (ECT) Sensor
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The Camshaft Position (CMP) Sensor
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The Mass Air Flow (MAF) Sensor
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The Manifold Absolute Pressure (MAP) Sensor
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The Heated Oxygen Sensors (HO2S)
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The fuel tank pressure sensor
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The fuel level sensor
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The diode module
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The Power Steering Pressure (PSP) Switch, if equipped
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The transmission range switch (A/T only)
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The Clutch Pedal Position (CPP) switch (M/T only)
For more information on some of the PCM input components refer to Information Sensors/Switches Description.
Output Components
The PCM is responsible for the control and operation of many output components. The PCM controls many components with an electronic switch that
completes a ground circuit when turned on. The PCM monitors the output components for the proper response to the PCM commands. Components
where functional monitoring is not feasible will be monitored for circuit continuity and out-of-range values if applicable.
Output components to be monitored include, but are not limited to, the following circuits:
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The Idle Air Control (IAC) Valve
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The main relay
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The Malfunction Indicator Lamp (MIL) control
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The up-shift indicator lamp
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The electronic transaxle controls
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The A/C compressor control module, or the A/C relay
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The cooling fan relay
For more information on some of the PCM output components, refer to PCM Outputs Description.
PCM EPROM
The PCM has an Erasable Programmable Read-only Memory (EPROM) computer chip that contains the calibration information used by the PCM to
control fueling, idle speed, ignition timing, transaxle shifts, and vehicle emissions. The calibration information is based on various aspects of the vehicle,
such as engine size, vehicle weight, transaxle type, final drive ratio, etc. The EPROM is programmed (flashed) with the calibration information that is
critical to the proper operation of the PCM. The EPROM is soldered into the PCM and cannot be serviced separately. Replacement PCMs used for
service come with all the necessary programming already installed.
Self-Diagnosis Function
The PCM diagnoses any troubles which may occur in the engine control system when the ignition switch is in the On position with the engine running.
The PCM indicates a malfunction by illuminating the Malfunction Indicator Lamp (MIL) when a fault occurs in any of the following systems:
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The Heated Oxygen Sensor 1 (HO2S 1)
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The Heated Oxygen Sensor 2 (HO2S 2)
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The Engine Coolant Temperature (ECT) sensor
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The Throttle Position (TP) sensor, including the CTP switch
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The Mass Air Flow (MAF) sensor
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The Vehicle Speed Sensor (VSS)
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The Intake Air Temperature (IAT) sensor
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The Manifold Absolute Pressure (MAP) sensor
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The Camshaft Position (CMP) Sensor
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The Crankshaft Position (CKP) Sensor
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The Evaporative Emission (EVAP) Control System
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The Idle Air Control (IAC) System
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The misfire detection
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The fuel trim
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The catalyst monitor
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The cooling fan control
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The Central Processing Unit (CPU) of the PCM
