Hombre S Regular Cab 4WD V6-4.3L (1999)
Body Control Module: Description and Operation
Body Control System Description
Familiarize yourself with the information and proper diagnosing procedures. The BCM diagnostic system check is an organized approach in order to
identify the cause of a condition that is reported by a BCM system malfunction code.
The BCM diagnostic system check is the starting point for diagnosis of any BCM system complaint. The BCM diagnostic system check will direct you to
the next logical step in diagnosing the complaint. Correct use of the table reduces diagnostic time and prevents unnecessary replacement of good parts.
The BCM is designed in order to perform the following functions:
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Process various input information
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Send the needed electrical responses to the other control modules
The input information is related to more than one output. If one input fails, the failure may affect the operation of more than one system.
The BCM controls the operation of the following components:
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The audible reminders
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The warnings
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The power door locks
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Interior lighting
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Exterior lighting
The BCM has features that permit the following functions:
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Timing out and turning OFF inadvertent loads
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Providing retained accessory power
The BCM is designed in order to interface with a remote function actuator (RFA) subsystem. The interface provides remote operation of certain features
of the vehicle. The BCM also provides vehicle security with an integrated Passlock (TM) system.
The BCM communicates via a Class 2 serial data bus. The communication enables diagnosis and programming at the assembly plant or an approved
service center.
The BCM supplies a buffered voltage to various sensors and switches through an internal resistance in the BCM. The resistance is so High in value that
an ordinary test lamp may not light when the lamp is connected to the circuit. An ordinary shop voltmeter may give an inaccurate reading because the
voltmeter input impedance is too low. Use a J 39200 Digital Multimeter (DMM) in order to ensure accurate voltage readings. Refer to Special Tools.
See: Tools and Equipment
