Scan Tool Communication With Any System Not Possible
- Disconnect scan tool from 16-pin Data Link Connector (DLC). See Figure . Using DVOM, measure voltage between ground and DLC terminal No. 16 (Red/Black wire). See Figure . If battery voltage is indicated, go to next step. If battery voltage is not indicated, repair faulty Red/Black wire or Red wire between DLC and fusible link No. 1 located in engine compartment.
- Using DVOM, check for continuity between ground and DLC terminals No. 4 and 5. If continuity is indicated at both terminals, repair scan tool. If continuity is not indicated at one or both terminals, repair open in suspect Black wire between DLC and ground.