Information Bus: Description and Operation

Warning Classification And Behavior:

Check Engine
The CHECK ENGINE warning information is sent by the Electronic Engine Control (EEC) EEC-IV module on the Data Communication Link (DCL).

Check DCL
This warning is displayed when there is a fault in the DCL system. Anytime a CHECK ENGINE (MIL) warning occurs refer to Computers and Control, System Diagnosis. If a CHECK DCL warning occurs without a CHECK ENGINE warning, refer to DCL Quick Test for diagnosis of the DCL.