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Data Link Connector: Testing and Inspection

DLC Circuit Troubleshooting

If the PCM does not communicate with the OBD II scan tool, Honda PGM Tester, or I/M test equipment, do this troubleshooting procedure.

1. Turn the ignition switch ON (II).





2. Measure voltage between data link connector (DLC) terminal No.16 and body ground.

Is there battery voltage?

YES - Go to step 3.

NO - Repair open in the wire between DLC terminal No.16 and the ACGS (15 A) fuse in the under-hood fuse/relay box.





3. Measure voltage between DLC terminal No.4 and No.16.

Is there battery voltage?

YES - Go to step 4.

NO - Repair open in the wire between DLC terminal No.4 and body ground.





4. Measure voltage between DLC terminals No.5 and No.16.

Is there battery voltage?

YES - Go to step 5.

NO - Repair open in the wire between DLC terminal No.5 and body ground.





5. Measure voltage between DLC terminals No.5 and No.7.

Is there 8.5 V or more?

YES - Go to step 10.

NO - Go to step 6.

6. Turn the ignition switch OFF.
7. Disconnect the PCM connector A (32P). Make sure the PGM Tester is disconnected from the DLC.





8. Check for continuity between DLC terminal No.7 and body ground.

Is there continuity?

YES - Repair short to ground in the wire between DLC terminal No.7 and the PCM (A21).

NO - Go to step 9.





9. Check for continuity between DLC terminal No.7 and PCM terminal A21.

Is there continuity?

YES - Substitute a known-good PCM and recheck. If the symptom/indication goes away, replace the original PCM.

NO - Repair open in the wire between DLC terminal No.7 and the PCM (A21).

10. Turn the ignition switch OFF.
11. Disconnect the PCM connector A (32P) Make sure the PGM Tester is disconnected from the DLC.
12. Turn the ignition switch ON (II).





13. Measure voltage between DLC terminals No.5 and No.7.

Is there 0 V ?

YES - Substitute a known-good PCM and recheck. If the symptom/indication goes away, replace the original PCM.

NO - Repair short to power in the wire between DLC terminal No.7 and PCM (A21).