Tracker 2WD L4-1.6L VIN 6 (2000)
Powertrain Control Module: Description and Operation
PCM (PCM Function)
Control Module Learning Ability
The control module has a "learning" ability which enables the control module to make corrections for minor variations in the fuel system. This learning
ability can improve driveability. Disconnecting the battery resets the learning process. A change in the vehicle's performance may be noticed when a
reset occurs. The vehicle operator can teach the control module in order to regain some of the lost vehicle performance.
In order to teach the control module, ensure that the engine is at operating temperature and drive the vehicle at part throttle with moderate acceleration.
The vehicle may also be operated at idle conditions until normal performance returns.
Fail-Safe Function
When a malfunction occurs within the engine control system, the PCM maintains control over the fuel injection system, the idle speed control system,
etc. The PCM controls these systems by using calculated values and backup programs stored within the PCM.
This function is called the fail-safe function. With the fail-safe function, a certain level of engine performance is available even when a malfunction
occurs. The fail-safe function prevents a complete loss of engine performance.
The systems covered by the fail-safe function are as follows:
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The Engine Coolant Temperature (ECT) Sensor
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The Throttle Position (TP) Sensor
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The Mass Air Flow (MAF) Sensor
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The Intake Air Temperature (IAT) Sensor
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The Vehicle Speed Sensor (VSS)
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The Barometric (BARO) Pressure Sensor
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The fuel level sensor
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The Central Processing Unit (CPU) in the PCM
General
Powertrain Control Module (PCM) Description
The Powertrain Control Module (PCM) is a precision unit consisting of a one chip microprocessor, an Analog/digital (A/D) converter, and an
Input/output (I/O) unit. The PCM is an essential part of the electronic control system. The PCM is responsible for such major functions as control of the
fuel injectors, the Idle Air Control (IAC) valve, the fuel pump relay, etc. The PCM performs the OBD 2 diagnostic tests of the emission related systems.
The PCM supplies a buffered voltage to the various information sensors and switches. The PCM controls most components with an electronic switch that
completes a ground circuit when turned on. The PCM is also responsible for a self-diagnosis function and a fail-safe function.
The PCM (1) is located below the glove box, underneath the instrument panel, on the right side of the passenger compartment.
Input Components
