Symptoms - Data Communications |
Important | ||
The following steps must be completed before using the symptom tables. | ||
1. |
Perform the Diagnostic System Check - Vehicle before using the symptom tables in order to verify that all of the following are true: |
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There are no DTCs set. |
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The control modules can communicate via the serial data links. |
2. |
Review the system operation in order to familiarize yourself with the system functions. Refer to Data Link Communications Description and Operation. |
Visual/Physical Inspection |
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Inspect for aftermarket devices which could affect the operation of the systems. Refer to Checking Aftermarket Accessories. |
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Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom. |
Intermittent |
Symptom List |
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Scan Tool Does Not Power Up
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Scan Tool Does Not Communicate with High Speed GMLAN Device
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Scan Tool Does Not Communicate with Mid Speed GMLAN Device
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Scan Tool Does Not Communicate with Low Speed GMLAN Device
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Scan Tool Does Not Communicate with Chassis High Speed GMLAN Device
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