Data Link Connector No. 3 Inspection
NOTE:
The vehicle's ECM uses ISO 9141-2 for communication. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.
- If the display shows UNABLE TO CONNECT TO VEHICLE when you have connected the cable of the OBD II scan tool or the hand-held tester to the DLC3, turned the ignition switch ON and operated the scan tool, there is a problem on the vehicle side or tool side.
- If the communication is normal when the tool is connected to another vehicle, inspect the DLC3 on the original vehicle.
- If the communication is still impossible when the tool is connected to another vehicle, the problem is probably in the tool itself, so consult the service department listed in the tool's instruction manual.
- Check DLC3 for loose or damaged terminals. Ensure DLC3 terminals are in correct position in connector. See Fig 1. Repair as necessary. If connector and terminals are okay, go to next step.
- Check voltage and resistance between ground and specified terminal on DLC3. See IDENTIFYING DLC3 VOLTAGE & RESISTANCE table. See Fig 1. If voltage and resistance readings are not as specified, check wiring circuit. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
IDENTIFYING DLC3 VOLTAGE & RESISTANCE
| Terminal No. (Circuit) | Voltage Or Resistance | Condition |
|---|---|---|
| 4 (Chassis Ground) - Body Ground | Less Than 1 Ω | Always |
| 5 (Signal Ground) - Body Ground | Less Than 1 Ω | Always |
| 7 (BUS Communication) | Pulse Generation | During Transmission |
| 16 (Battery Voltage) - Body Ground | 9-14 V | Always |