Description of On-Board Diagnostics

Operation
When troubles occur in the main input devices or output devices of the engine control system, they are recorded in the memory of the powertrain control module engine (PCME).
Failures of each input and output device are indicated and retrieved from the PCME as diagnostic trouble code (DTC) numbers.

NOTE: For input devices, the PCME continuously checks for malfunctions. For output devices, it checks for malfunctions only in a three-second period after the ignition switch is turned to ON, or the "TEN" terminal in the data link connector is grounded.

View: Special Service Tools:

DTC Retrieval
DTCs can be retrieved from PCME memory by using the special service tools (SST) shown in the accompanying image.
For more information on DTC retrieval see: How to Display and Read Diagnostic Trouble Codes.