GM 91176710
ECM

The service programming system (SPS) uses the data link connector (DLC) to let technicians program control modules through the serial data circuit that also enables scan tool retrieval of diagnostic trouble codes (DTCs) and data presentation functions. During programming a control module contains electrically erasable programmable read only memory (EEPROM) and flash read only memory as storage types. Eeprom keeps learned data including vehicle identification number (VIN) along with crankshaft variation learned position, software/calibration ids and security codes. However, flash read only memory serves as primary storage due to its capacity size along with complete data wiping for new programming content. The control module along with the programming equipment of (Tech 2) exists in four different setups that include remote programming using (Tech 2), pass thru programming using (Tech 2), off-board remote programming with (OBPA) and (Tech 2), and off-board pass thru programming with (OBPA) and (Tech 2). Both installed and non-installed cases are valid. Perform the vehicle programming process only when the battery voltage stays within 12 to 16 volts and there are no issues with the charging system and daytime running lights and all hvac systems and engine cooling fans are in off mode. The scan tool will determine when to position the Ignition Switch while the dl reference cable and connected rs-232 components require proper securement. Disturbing the tool harnesses during programming should be avoided to prevent programming failures or tool harm. Programming the powertrain system will lead to new operating characteristics that cause the control module to perform value learning processes for fuel trim corrections and idle air control learned positions and automatic transmission shift adaptations. When replacing a control module the technician must perform multiple additional service tasks including crankshaft variation learn and engine oil life reset and idle learn in addition to inspection/maintenance complete system set and vehicle theft deterrent password learn and Throttle Position Sensor learn.