Cutlass Supreme V6-204 3.4L DOHC VIN X SFI (1995)
Serial Data: Description and Operation
There are two data lines that can be accessed with a Scan Tool. The 800 circuit data line is the Powertrain Control Module (PCM) Data Line. It allows
the PCM, Inflatable Restraint Diagnostic Energy Reserve Module with Sensor (SDM), Electronic Brake Control Module (EBCM) (if equipped), Trip
Computer (Pontiac) and Heater and A/C Control (CJ2) to communicate by transmitting data through CKT 800. The 835 Circuit Data Line is
entertainment and comfort (E & C Bus) Data line. It allows the Radio and/or Heater and A/C Control to communicate via CKT 835.
A scan tool can be connected to the Data Link Connector (DLC); this allows the scan tool to communicate with the PCM Data Line. System operations
can then be monitored for diagnostic purposes.
Security Indicator (SEO)
The Special Equipment Option (SEO) Theft Deterrent Module is unprogrammed under normal conditions and will provide a pulsed ground in
CKT 728 when the Ignition Switch is in "RUN", "BULB TEST" or "START" If a fault is determined, the Theft Deterrent Module will ground
CKT 728.
