Data Link Connector: Testing and Inspection
DLC Circuit TroubleshootingIf the ECM does not communicate with a scan tool, the HDS, or I/M test equipment, do this troubleshooting procedure.
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. 8 and the ACGS (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. 8 and body ground (G401).
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. 8 and body ground (G101).
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). Make sure the scan tool or the HDS 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. 15 and the ECM (A21). After repairing the wire, check for DTCs 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. 15 and ECM terminal A21.
Is there continuity?
YES - Substitute a known-good ECM and recheck. If the symptom/indication goes away, replace the original ECM.
NO - Repair open in the wire between DLC terminal No. 7 and the ECM (A21). After repairing the wire, check for DTCs 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). Make sure a scan tool or the HDS 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 ECM and recheck. If the symptom/indication goes away, 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 for DTCs with a scan tool or the HDS, and go to the indicated DTC's troubleshooting.