"Generic" OBD II Scan Tool Information
A new Intellegant Saab Tester (ISAT) menu option for 1996 is GST (Generic Scan Tool), the information is displayed here as it will appear on a generic scan tool. Here are the menu choices which will come up when you select GST.OBD II
^ READ CURRENT DATA
^ READ FREEZE FRAME
^ READ FAULT CODES
^ CLEAR FAULT CODES
Freeze Frame
OBD II diagnostic systems will record freeze frame data in the appropriate ECM at the instant an emissions-related fault is detected but this information will not be accessible until and the MIL is commanded ON. Freeze frame data is part of the information which must be displayed on any "generic" scan tool. To read the freeze frame with ISAT you must call up the GST menu. Keep in mind that this information represents only the operating conditions at the instant that the fault was first detected. This function does not provide the "snapshot" or "movie" capability found in some other systems to review data acquired before and after the event.
The contents of a freeze frame include:
^ The DTC which initiated the freeze frame
^ Closed loop status
^ Calculated load value
^ Engine coolant temperature
^ Intake air temperature
^ Short term fuel trim
^ Long term fuel trim
^ Intake manifold pressure
^ Engine RPM
^ Vehicle speed