Sebring Sedan V6-2.7L VIN R (2004)
position of the switch. The BCM then supplies the ground path for the up or down relay as requested. The power top switch has a 4.7 K-ohm diagnostic
resistor that allows the BCM to detect a possible open circuit.
WINDOW DROP RELAY ASSEMBLY
The convertible has a feature that allows the operator to lower all four windows and lower the top at the same time. This is accomplished by pressing the
power top switch to the second detent. Through the multiplexed circuit of the power top switch the BCM will supply the ground for the window drop
relay assembly.
The window drop relay assembly is comprised of four separate relays that are in series with the power window circuits. The relay assembly is located in
the driver door.
Communication
The Programmable Communication Interface or PCI Bus is a single wire multiplexed network capable of supporting binary encoded messages shared
between multiple modules. The PCI bus circuit is identified as D25. The modules are wired in parallel. Connections are made through the BCM. The
BCM acts as a splice to connect each module and the Data Link Connector (DLC) together. The following modules are used on JR:
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Airbag Control Module or referred to as the Occupant Restraint Controller (ORC)
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Automatic Temperature Control Module
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Controller Antilock Brake
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Powertrain Control Module
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Radio (if equipped)
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CD Changer (if equipped)
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Compass/Mini-Trip Computer (if equipped)
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Body Control Module
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Sentry Key Immobilizer Module
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Transmission Control Module
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Mechanical Instrument Cluster
Each module provides its own bias and termination in order to transmit and receive messages. The bus voltage is at zero volts when no modules are
transmitting and is pulled up to about seven and a half volts when modules are transmitting.
The bus messages are transmitted at a rate averaging 10800 bits per second. Since there is only voltage present when the modules transmit and the
message length is only about 500 milliseconds, it is ineffective to try and measure the bus activity with a conventional voltmeter. The preferred method
is to use the DRBIII(R) lab scope. The 12v square wave selection on the 20-volt scale provides a good view of the bus activity. Voltage on the bus
should pulse between zero and about seven and a half volts. Refer to the following figure for some typical displays.
