Vibe FWD L4-2.4L (2009)
The PCM will begin to count the warm-up cycles when the fault that caused the DTC to be stored into memory has been corrected. The DTC will
automatically be cleared from the PCM memory when the PCM has counted 40 consecutive warm-up cycles with no further faults detected.
Diagnostic trouble codes (DTCs) can be cleared using a scan tool. In order to clear DTCs, use the scan tools Clear DTC Information function. Follow the
instructions supplied by the scan tool manufacturer.
Aftermarket (Add-On) Electrical and Vacuum Equipment
Caution: Connect any add-on electrically operated equipment to the vehicle's electrical system at the battery (power and ground) in order to prevent
damage to the vehicle.
Caution: Do not attach add-on vacuum operated equipment to this vehicle. The use of add-on vacuum equipment may result in damage to vehicle
components or systems.
Aftermarket (add-on) electrical and vacuum equipment is defined as any equipment installed on a vehicle after leaving the factory that connects to the
vehicles electrical or vacuum systems. No allowances have been made in the vehicle design for addition of this type of equipment.
Add-on electrical equipment may cause the engine control system to malfunction even when the add-on electrical equipment is installed properly.
Portable telephones and radios may also cause engine control system malfunctions even when not connected to the vehicles electrical system. The first
step in diagnosing any engine control system problem is to remove all aftermarket electrical equipment from the vehicle. Diagnosis may proceed in the
normal manner after eliminating aftermarket equipment as a cause of the engine control system malfunction.
Electrostatic Discharge (ESD) Damage
Caution: In order to prevent possible Electrostatic Discharge damage to the PCM, Do Not touch the connector pins or the soldered components on the
circuit board.
Electronic components used in the engine control system are often designed to operate at very low voltages. Electronic components are susceptible to
damage caused by electrostatic discharge. Less than 100 volts of static electricity can cause damage to some of the electronic components. There are
several ways for a person to become statically charged. The most common methods of charging are by friction and by induction. An example of charging
by friction is a person sliding across a car seat. Charging by induction occurs when a person with well insulated shoes stands near a highly charged object
and momentarily touches ground. Charges of the same polarity are drained off leaving the person highly charged with the opposite polarity. Therefore,
use care when handling and testing electronic components in order to avoid electrostatic charges that can cause electronic component damage.
Input Components
The PCM supplies a buffered (reference) 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 crankshaft position (CKP) sensor
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The accelerator pedal position (APP) sensors
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The throttle position (TP) sensors
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The engine coolant temperature (ECT) sensor
*
The camshaft position (CMP) sensor
*
The mass air flow (MAF) sensor
*
The heated oxygen sensor (HO2S)
*
The fuel tank pressure (FTP) sensor
*
The knock sensor (KS)
*
The vehicle speed sensor (VSS)
*
The power steering pressure (PSP) switch, if equipped
*
The transmission range switch (A/T only)
*
The A/C compressor control module (A/C relay)
Output Components
The PCM is responsible for the control and operation of many output components. The PCM controls many components with an electronic switch called
an output driver 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 CMP actuator solenoid valve
*
The circuit opening or fuel pump relay
