Silhouette V6-3.4L VIN E (1996)
Engine Control Module: Description and Operation
Powertrain Control Module (PCM)
General Description
Figure C1-1 - Powertrain Control Module (PCM)
Controls the following:
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Fuel metering system.
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Transaxle shifting.
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Ignition timing.
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On-board diagnostics for Powertrain functions. It constantly looks at the information from various sensors, and controls the systems that affect
vehicle performance. The PCM also performs the diagnostic function of the system. It can recognize operational problems, alert the driver
through the MIL, and store diagnostic trouble codes which identify the problem areas to aid the technician in making repairs.
VIN E RPO LA1 engines use a PCM 32U. For service, the PCM consists of two parts: a controller (the PCM without the Knock Sensor module) and
the Knock Sensor module.
Circut Description
The PCM is responsible for maintaining proper spark and fuel injection timing for all driving conditions. Ignition Control (IC) spark timing is the PCM
method of controlling spark advance and ignition dwell. To provide optimum driveability and emissions, the PCM monitors input signals from the
following components in calculating Ignition Control (IC) spark timing:
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Ignition Control module (ICM).
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Engine Coolant Temperature (ECT) sensor.
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Intake Air Temperature (IAT) sensor.
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Mass Air Flow (MAF) sensor.
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Trans Range or PNP inputs from Trans Range switch or Park/Neutral Position switch.
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Throttle Position (TP) sensor.
