Trooper S 2WD V6-3.5L (2001)
Engine Control Module: Description and Operation
Powertrain Control Module (PCM)
Powertrain Control Module (PCM)
The powertrain Control module (PCM) is located in the passenger compartment below the center console.
The PCM Controls the following:
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Fuel metering system.
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Transmission shifting (automatic transmission only).
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Ignition timing.
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On-board diagnostics for powertrain functions.
The PCM constantly observes the information from various sensors. The PCM Controls the systems that affect vehicle performance. The PCM performs
the diagnostic function of the system. It can recognize operational problems, alert the driver through the MIL (Check Engine lamp), and store diagnostic
trouble codes (DTCs). DTCs identify the problem areas to aid the technician in making repairs.
PCM Components
PCM Components
The PCM is designed to maintain exhaust emission levels to government mandated standards while providing excellent driveability and fuel efficiency.
The PCM monitors numerous engine and vehicle functions via electronic sensors such as the throttle position (TP) sensor, heated oxygen sensor (HO2S),
and vehicle speed sensor (VSS). The PCM also Controls certain engine operations through the following:
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Fuel injector Control
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Ignition Control Module
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ION sensing module
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Automatic transmission shift functions
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Cruise Control
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Evaporative emission (EVAP) purge
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A/C clutch Control
The PCM is responsible for maintaining proper spark and fuel injection timing for all driving conditions. To provide optimum driveability and
emissions, the PCM monitors the input signals from the following components in order to calculate spark timing:
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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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PRNDL input from transmission range switch.
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Throttle position (TP) sensor.
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Vehicle speed sensor (VSS).
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Crankshaft position (CKP) sensor.
PCM Function
PCM Function
