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)

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Check DLC3

CHECK DLC3










The vehicle uses ISO 15765-4 communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format.

HINT: If the display shows "UNABLE TO CONNECT TO VEHICLE" when the cable of the intelligent tester is connected to DLC3, the ignition switch is turned ON and the intelligent tester is operated, there is a problem either on the vehicle side or the tester side.
- If communication is normal when the tester is connected to another vehicle, inspect DLC3 on the original vehicle.
- If communication does not function when the tester is connected to another vehicle, the problem is probably in the tester itself. So consult the Service Department listed in the tester's instruction manual.