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DLC Circuit Troubleshooting

DLC Circuit Troubleshooting

NOTE:
- If the MCM does not communicate with the HDS, do this troubleshooting procedure.
- Check that the IMA system indicator 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. 8 FI ECU (PCM) (15 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 G501




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 G503

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 13.

NO - Go to step 6.

6. Turn the ignition switch OFF.
7. Turn the battery module switch OFF.
8. Remove the IPU lid.
9. Disconnect MCM connector B (24P). Make sure the HDS is disconnected from the DLC.




10. 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 MCM (B17). After repairing the wire, check for a DTC with the HDS. If there is a DTC, go to the DTC Troubleshooting.

NO - Go to step 11.




11. Connect DLC terminal No. 7 to body ground with a jumper wire.




12. Check for continuity between MCM terminal B17 and body ground.

Is there continuity?

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

NO - Repair open in the wire between DLC terminal No. 7 and the MCM (B17). After repairing the wire, check for a DTC with the HDS. If there is a DTC, go to the DTC Troubleshooting.

13. Turn the ignition switch OFF.
14. Turn the battery module switch OFF.
15. Remove the IPU lid.
16. Disconnect MCM connector B (24P). Make sure the HDS is disconnected from the DLC.
17. Turn the ignition switch ON (II).




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

Is there 0 V?

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

NO - Repair short to power in the wire between DLC terminal No. 7 and the MCM (B17). After repairing the wire, check for a DTC with the HDS. If there is a DTC, go to the DTC Troubleshooting.