Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnosis System
- DESCRIPTION
- The defogger system data can be read from the Data Link Connector 3 (DLC3) of the vehicle. When the system seems to be malfunctioning, use the intelligent tester to check for malfunctions and perform repairs.
- CHECK DLC3
- The vehicle uses the ISO 15765-4 for communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format.
Standard voltage
TERMINAL SPECIFICATION TABLE (VOLTAGE)Symbol (Terminal No.) Terminal Description Condition Specified Condition SIL (7) - SG (5) Bus "+" line During transmission Pulse generation BAT (16) - Body ground Battery positive Always 10 to 14 V Standard resistance
TERMINAL SPECIFICATION TABLE (RESISTANCE)Symbol (Terminal No.) Terminal Description Condition Specified Condition CG (4) - Body ground Chassis ground Always Below 1 ohms SG (5) - Body ground Signal ground Always Below 1 ohms CANH (6) - CANL (14) HIGH-level CAN bus line Engine switch off 54 to 67 ohms CANH (6) - Body positive (+) HIGH-level CAN bus line Engine switch off 1 M ohms or higher CANH (6) - CG (4) HIGH-level CAN bus line Engine switch off 3 M ohms or higher CANL (14) - Body positive (+) LOW-level CAN bus line Engine switch off 1 M ohms or higher CANL (14) - CG (4) LOW-level CAN bus line Engine switch off 3 M ohms or higher If the result is not as specified, the DLC3 may have a malfunction. Repair or replace the harness and connector.
HINT:
Connected the cable of the intelligent tester (with CAN VIM) to the DLC3, turn the engine switch on (IG) and attempt to use the intelligent tester. If the display indicates that a communication error has occurred, there is a problem either with the vehicle or with the intelligent tester.
- If communication is normal when the tester is connected to another vehicle, inspect the DLC3 of the original vehicle.
- If communication is still not possible when the tester is connected to another vehicle, the problem may be in the intelligent tester itself. Consult the Service Department listed in the tester's instruction manual.
- The vehicle uses the ISO 15765-4 for communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format.
- CHECK BATTERY VOLTAGE
Standard voltage: 11 to 14 V
If the voltage is below 11 V, recharge or replace the battery before proceeding.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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