Cavalier/Z24 L4-144 2.4L DOHC VIN T SFI (1996)
Serial Data: Component Tests and General Diagnostics
Circuit Operation
There are two data lines that can be accessed with a scan tool. The Serial Data Line (UART) (800 CKT) allows the scan tool (when connected),
Powertrain Control Module
(PCM), Instrument Cluster (I/P), Diagnostic Energy Reserve Module (DERM), and the Electronic Brake Control Module
(EBCM) to communicate via serial data. The Serial Data Line (Class 2) (1807 CKT) allows a scan tool to directly access the Powertrain Control Module
to read emissions related information. A scan tool can gain access to both data lines through the Data Link Connector
(DLC). System operations can
then be monitored or controlled for diagnostic purposes.
Chart #1 Serial Data Line Diagnosis (Part 1 Of 2)