Inspection Procedure 1

Communication with Scan Tool Is Not Possible. (Communication with All Systems Is Not Possible.)

Data Link Connector Circuit Part 1:

Data Link Connector Circuit Part 2:

CIRCUIT OPERATION
- A battery positive voltage is applied on the data link connector power terminal (terminal No. 16). The ground terminals (terminal No. 4, No. 5) are grounded to the vehicle body.

COMMENT
- The cause is probably a defect in power supply system (including ground) for the on-board diagnostic test mode line.

TROUBLESHOOTING HINTS (The most likely causes for this case:)
- Malfunction of the data link connector.
- Damaged harness wire.

DIAGNOSIS

STEP 1. Measure the power supply voltage at data link connector C-29.







1. Measure voltage between terminal No. 16 and ground.
- Voltage should be battery positive voltage.

Q: Is battery positive voltage (approximately 12 volts) present?

YES: Go to step 2.

NO: Check harness connectors C-108, C-113 and C-89 at intermediate connector for damage and repair or replace as required. Refer to Harness Connector Inspection. If intermediate connectors are in good condition, repair harness wire between fusible link 1 and data link connector C-29 (terminal No. 16) because of open circuit. Then confirm that the malfunction symptom is eliminated.

STEP 2. Check the continuity at data link connector C-29.







1. Check for the continuity between terminal No. 4, No. 5 and ground.
- Should be less than 2 ohms.

Q: Is the continuity normal?

YES: Replace the scan tool. Then confirm that the malfunction symptom is eliminated.

NO: Repair harness wire between data link connector C-29 (terminal No. 4, No. 5) and ground because of open circuit or harness damage. Then confirm that the malfunction symptom is eliminated.