Inspection Procedure 1

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 (terminals 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-14.







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

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

YES: Go to step 2.

NO: Check harness connectors C-126, C-212 and C-214 at intermediate connector for damage, and repair or replace as required. If intermediate connectors are in good condition, repair harness wire between fusible link (1) and data link connector C-14 (terminal No. 16) because of open circuit. Then confirm that the malfunction symptom is eliminated.

STEP 2. Check for continuity at data link connector C-14.







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

Q: Does continuity exist?

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

NO: Repair harness wire between data link connector C- 14 (terminals No. 4, No. 5) and ground because of open circuit or harness damage. Then confirm that the malfunction symptom is eliminated.