Scan Tool Testing and Procedures

Engine Controls Schematics: MIL And Data Link Connector:

CIRCUIT DESCRIPTION

Modules connected to the Class II 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 DLC allows communication with the modules for diagnostic purposes. Diagnostic Trouble Codes (DTCs) may be set due to this symptom and during this diagnostic procedure. Complete the diagnostic procedure in order to ensure all the DTCs are diagnosed and cleared from memory.

Diagnostic Charts:

DIAGNOSTIC AIDS
^ When the Class II serial data circuit is shorted to ground, U1300 or U1305 will be set. Refer to DTC U1300 Class 2 Data Link Low or DTC U1305 Class 2 Data Link Low or High in Data Link Connector. Testing and Inspection

^ When the Class II serial data circuit is shorted to battery positive voltage U1301 or U1305 will be set. Refer to DTC U1301 Class 2 Data Link High or DTC U1305 Class 2 Data Link Low or High in [1][2]Data Link Communications. Testing and Inspection