Scan Tool Communication With All Systems Not Possible
- Measure voltage at Data Link Connector (DLC) terminal No. 16 (Red/Black wire). See WIRING DIAGRAMS . If battery voltage does not exist, go to next step. If battery voltage exists, go to step 3.
- Check fuse and connections in engine compartment relay box. See WIRING DIAGRAMS . Repair fuse/wiring as necessary. If fuse and connections are okay, repair open Red/Black wire.
- Check for continuity between ground and DLC terminals No. 4 (Black wire) and No. 5 (Black/White wire). If continuity does not exist, repair open ground circuit. If continuity exists, replace scan tool.