Diagnostic System Check
DIAGNOSTIC SYSTEM CHECKDESCRIPTION
The Diagnostic System Check-Computers and Control Systems is an organized approach to identifying a condition that is created by a malfunction in the engine control system. The Diagnostic System Check must be the starting point for any driveability concern. The Diagnostic System Check directs the service technician to the next logical step in order to diagnose the concern. Understanding and correctly using the diagnostic table reduces diagnostic time and prevents the replacement of good parts.
TEST DESCRIPTION
Steps 1-8:
Steps 9-13:
The numbers below refer to the step numbers on the diagnostic table.
3. The Data Link References table is to identify which serial data protocol a particular control module is using. The powertrain control module (PCM) utilizes keyword serial data and controller area network (CAN) serial data.
11. This step is for areas that have inspection and maintenance testing procedures for emissions testing. Use this step if the testing facility found one or more I/M system statuses that did not set.