Power Door Locks
Important Preliminary Checks Before Starting:
- Perform A Diagnostic System Check - Door Systems before using
the symptom tables in order to verify that all of the following are true:
| • | The body control module (BCM) can communicate via the serial data
link. |
- Review the system operation in order to familiarize yourself with
the system functions. Refer to the following:
| • | Power doors circuit description |
| • | Power doors system operation |
Visual/Physical Inspection
Several of the symptom procedures ask for a careful visual/physical
check. This step is extremely important-it could lead to correcting a problem
without further checks and can save valuable time. These checks include
the following:
| • | Inspect for aftermarket devices which could affect the operation
of the Power Door Systems. Refer to Checking Aftermarket Accessoriesin Wiring
Systems. |
| • | Inspect the easily accessible or visible system components and
harness connectors for obvious damage or conditions which could cause the
symptom. |
Intermittents
Important: Check for proper installation of electrical components if an intermittent
condition exists. Inspect for aftermarket theft deterrent devices, lights
and cellular phones. Ensure that no aftermarket equipment is connected
to the class 2 circuit. If you can not locate an intermittent condition,
a cellular phone signal may cause the condition. Faulty electrical
connections or wiring may also be the cause of intermittent conditions.
Refer to Testing for Intermittent and Poor Connections in Wiring Systems.
Important: The problem may or may not turn on the SERVICE VEHICLE SOON indicator
or store a DTC. Do not use the symptom tables to diagnose intermittent conditions.
The malfunction must be present in order to locate the problem.
Poor electrical connections or wiring cause most intermittent conditions.
Perform a careful visual/physical check for the following conditions:
| • | Poor mating of the connector halves or a terminal not fully seated
in the connector body (backed out). |
| • | An improperly formed or damaged terminal. |
| • | Reform or replace connector terminals in the problem circuit in
order to insure proper contact tension. |
| • | Poor terminal to wire connection requires removing the terminal
from the connector body in order to perform the check. |
Road test the vehicle with a J 39200 digital multimeter (DMM) connected
to the suspected circuit. An abnormal voltage when the malfunction occurs
is a good indication that there is a malfunction in the circuit being
monitored.
Use a Scan Tool in order to help detect intermittent conditions. The
scan tool has several features that can be used to locate an intermittent
condition. The snapshot feature can capture and store data parameters
within the scan tool when the malfunction occurs. This information
can then be reviewed in order to see what caused the malfunction.
Symptom List
Refer to Power Door Locks Inoperative in order to diagnose a symptom
that does not set a DTC.
Power Windows and Power Mirrors
Important: Review the system operation in order to familiarize yourself with the
system functions. Refer to the following:
| • | Power Windows Description |
| • | Power Windows Operation |
| • | Power Windows Circuit Description |
| • | Power Mirrors Description |
| • | Power Mirrors Operation |
| • | Power Mirrors Circuit Description |
Visual/Physical Inspection
| • | Inspect the easily accessible or visible system components for
obvious damage or conditions which could cause the symptom. |
Intermittent
Faulty electrical connections or wiring may be the cause of intermittent
conditions. Refer to
Testing for Intermittent Conditions and Poor Connections
Symptom List
Refer to a symptom diagnostic procedure from the following list in order
to diagnose the symptom:
| • | Power Mirrors-Folding Inoperative |
| • | Power Mirrors Inoperative |
| • | Power Windows Inoperative-Express |
| • | Power Windows Inoperative |
| • | Power Window Inoperative from Passenger Door Switch |
