Data Link Connector: Testing and Inspection

DLC Circuit Troubleshooting

- If the ECM does not communicate with a scan tool or the HDS, do this troubleshooting procedure.
- Check that MIL circuit is normal, then do this troubleshooting.




1. Measure voltage between DLC terminal No. 16 and body ground.

Is there battery voltage?

YES - Go to step 2.

NO - Repair open in the wire between DLC terminal No. 16 and the No. 18 (7.5 A) fuse in the under-hood fuse/relay box.




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

Is there battery voltage?

YES - Go to step 3.

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




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

Is there battery voltage?

YES - Go to step 4.

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

4. Turn the ignition switch ON (II).




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 ECM connector A (32P).




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 ECM (A21). After repairing the wire, check the DTC with a scan tool or the HDS and go to the indicated DTC's Troubleshooting.

NO - Go to step 9.




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

Is there continuity?

YES - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.

NO - Repair open in the wire between DLC terminal No. 7 and the ECM (A21). After repairing the wire, check the DTC with a scan tool or the HDS and go to the indicated DTC's Troubleshooting.

10. Turn the ignition switch OFF.
11. Disconnect ECM connector A (32P).
12. Turn the ignition switch ON (II).




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

Is there 0 V?

YES - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.

NO - Repair short to power in the wire between the DLC terminal No. 7 and the ECM (A21). After repairing the wire, check the DTC with a scan tool or the HDS and go to the indicated DTC's Troubleshooting.