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.
Scan Tool Usage
The skid control ECU uses ISO 14230 for communication. The terminal arrangement of DLC3 complies with SAE J1962 and matches the ISO 14230 format. See Fig 1.
If the display shows "UNABLE TO CONNECT TO VEHICLE" when the LEXUS hand-held tester cable is connected to DLC3, the ignition switch is turned ON and the hand-held tester is operated, there is a problem on the vehicle side or the tester side. If communication is normal when the tester is connected to another vehicle, the problem is probably the tester itself. Consult the service department listed in the tester's operator's manual. For DLC3 connector identification see DLC3 Connector Identification .
| Terminal No. | Connection | Voltage Or Resistance | Condition |
|---|---|---|---|
| 7 | Bus & Line | Pulse Generation | During Transmission |
| 4 | Chassis Ground | Body Ground 1 Ohm or less | Always |
| 5 | Signal Ground | Body Ground 1 Ohm or less | Always |
| 16 | Battery Positive | Body Ground 9-14 Volts | Always |
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.