DESCRIPTION & OPERATION
| WARNING | Vehicles are equipped with air bag supplemental restraint system. Before attempting any repairs involving steering column, instrument panel or related components, see SERVICE PRECAUTIONS and DISABLING & ACTIVATING AIR BAG SYSTEM in AIR BAG RESTRAINT SYSTEM article. |
| CAUTION | When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION before disconnecting battery. |
The 800 circuit allows the Diagnostic Energy Reserve Module (DERM) and PCM to communicate with each other and a scan tool. A scan tool can be connected to the DLC, allowing the scan tool to communicate with the components on the data line. System operations can then be monitored for diagnostic purposes.
See also:
• COMPUTER RELEARN PROCEDURES