Troubleshooting Hints - Data Line
1. Check for proper connection of Scan Tool to Data Link Connector (DLC).2. Check for loose or missing terminals at DLC.
3. If Vehicle Control Module (VCM) is not accessible with a Scan Tool, check for an open in PPL, (1807) wire between component and DLC terminal 2.
4. If Electronic Brake Control Module is not accessible with a Scan Tool, check for an open in TAN/WHT (799) wire between component and DLC terminal 12.
5. If Inflatable Restraint Sensing Diagnostic Module is not accessible with a Scan Tool. check for an open in TAN (800) wire between component and DLC terminal 9.
6. Check for proper installation of aftermarket electronic equipment that may affect the integrity of other systems.
^ CHECK for a broken (or partially broken wire inside of the insulation which could cause system malfunction but prove GOOD in a Continuity/Voltage check with a system disconnected. 'These Circuits may be intermittent or resistive when loaded. and if be possible should be checked by monitoring for a Voltage drop with the system operational (under load).
^ CHECK for proper installation of aftermarket electronic equipment which may affect the integrity of other system (Refer to Troubleshooting Procedures). Diagnostic Aids