Scan Tool Does Not Power Up: Description

Modules connected to the Class 2 serial data circuit monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. Connecting a Scan Tool to the Data Link Connector (DLC) allows communication with the modules for diagnostic purposes. The diagnostic procedure assumes that all modules are powered. To ensure modules are properly powered, perform the Diagnostic System Check for the module in question. Diagnostic Trouble Codes (DTC) may be set due to this symptom and during this diagnostic procedure. Complete the diagnostic procedure in order to ensure that all the DTCs are diagnosed and cleared from memory.