Circuit Description
The data link connector (DLC) provides operating power for the scan tool at terminal 16 (battery positive voltage) and a power ground at terminal 4. The DLC provides the class 2 serial data signal at terminal 2 and a dedicated signal ground at terminal 5. The scan tool will power up with the ignition off.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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The C/LALDL fuse supplies power to the DLC terminal 16.
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The DLC battery positive voltage and ground circuits are functioning properly. The malfunction must be due to the scan tool.
Step | Action | Yes | No |
|---|---|---|---|
Test the battery positive voltage circuit of the DLC for an open or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Control Module References in Body Control System for the applicable Diagnostic System Check | Go to Step 2 | |
2 | Test the ground circuit of the DLC terminal 4 for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Control Module References in Body Control System for the applicable Diagnostic System Check | Go to Step 3 |
3 | Inspect for poor connections at the DLC terminals 4 and 16. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Control Module References in Body Control System for the applicable Diagnostic System Check | Go to Step 4 |
The scan tool may be malfunctioning. Refer to the scan tool instruction manual. Did you obtain a properly operating scan tool? | Go to Control Module References in Body Control System for the applicable Diagnostic System Check | -- |
