Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Scan Tool Testing and Procedures

Diagnostic Chart:




Refer to [1][2]Data Link Communications Schematic, and Data Link Communications Schematic.

CIRCUIT 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 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 AIDS
^ When the Class 2 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. Testing and Inspection Testing and Inspection
^ When the Class 2 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. Testing and Inspection Testing and Inspection