The service programming system (SPS) allows a technician
to program a control module through the data link connector (DLC). The information
transfer circuit that is used at the DLC is the same serial data circuit
used by the scan tool for retrieving diagnostic trouble codes (DTCs), displaying
data, clearing DTCs, etc. This procedure offers the ability to install
software/calibrations matched to a particular vehicle.
Most control modules have 2 types of memory. The software/calibrations
reside in the flash memory. The two types of memory are listed below:
| • | Electrically Erasable Programmable Read Only Memory (EEPROM) |
| | This type of memory allows selected portions of memory to be programmed
while other portions remain unchanged. |
| | Certain learned values reside in the EEPROM, such as: |
| • | The vehicle identification number (VIN) |
| • | The crankshaft variation learned position |
| • | The software/calibrations identification numbers |
| • | The control module security information |
| • | Flash Read Only Memory - Flash Memory |
| | Flash memory has increased memory storage capacity. During programming,
all information within this type of memory is erased, and then replaced
with entirely new information. |
Service Programming Methods
The 4 methods of programming a control module and the proper tools
for each method are as follows:
| - | The Tech 2 or other scan tool, Techline Terminal or a personal
computer equipped with General Motors Corporation authorized programming
software--The Tech 2 or other scan tool is used as an interface
between the vehicle and the Techline Terminal or a personal computer. |
| - | The control module is installed in the vehicle |
| - | The Tech 2 or other scan tool, Techline Terminal or a
personal computer equipped with General Motors Corporation authorized programming
software--The Tech 2 or other scan tool is used as an interface
between the vehicle and the Techline Terminal or a personal computer. |
| - | The control module is installed in the vehicle. |
| • | Off-Board Remote Programming, vehicle NOT available: |
| - | The Tech 2 or other scan tool, off-board programming adapter
(OBPA), Techline Terminal or a personal computer equipped with General Motors
Corporation authorized programming software--The Tech 2 or
other scan tool is used as an interface between the vehicle and the Techline
Terminal or a personal computer. |
| - | The control module is NOT installed in a vehicle |
| • | Off-Board Pass Thru Programming |
| - | The Tech 2 or other scan tool, off-board programming adapter
(OBPA), Techline Terminal or a personal computer equipped with General Motors
Corporation authorized programming software--The Tech 2 or
other scan tool is used as an interface between the vehicle and the Techline
Terminal or a personal computer. |
| - | The control module is NOT installed in a vehicle |
Before Programming a Control Module
Important: DO NOT program an existing control module with the identical software/calibration
package. This procedure is not a short cut to correct a driveability condition.
This is an ineffective repair. A control module should only be programmed
when the following occurs:
| • | When a service procedure instructs you to replace the control
module. The service part control module does not contain operating software
or calibrations. |
| • | General Motors Corporation releases an updated software/calibration
package. |
Ensure that the following conditions are met before programming a control
module:
| • | Vehicle system voltage: |
| - | There are no charging system concerns. All charging system concerns
must be repaired before programming a control module. |
| - | The battery voltage is greater than 12 volts but less than
16 volts. The battery must be fully charged before programming the
control module. |
| - | A battery charger is NOT connected to the vehicles battery. Incorrect
system voltage or voltage fluctuations from a battery charger may cause
programming failure or control module damage. |
| - | Turn OFF or disable any system that may put a load on the vehicles
battery. Turn OFF or disable systems such as: |
| • | Daytime running lights (DRL). Applying the parking brake, on most
vehicles, disables the DRL system. |
| • | Heating, ventilation, and air conditioning (HVAC) systems |
| • | Engine cooling fans, etc. |
| • | The ignition switch is in the proper position. The scan tool prompts
you to turn ON the ignition, with the engine OFF. DO NOT change the position
of the ignition switch during the programming procedure unless instructed
to do so. |
| • | All tool connections are secure: |
| - | The connection at the DLC |
| - | The voltage supply circuits |
| • | DO NOT disturb the tool harnesses while programming. If an interruption
occurs during the programming procedure, programming failure or control
module damage may occur. |
| • | If you are performing the pass-through programming procedure using
a notebook computer without the power cord, ensure that the internal battery
is fully charged. |
After Programming a Control Module
The powertrain may operate slightly different after a control module
software/calibration update. Operating the powertrain through various driving
conditions allows the control module to re-learn certain values. The control
module must re-learn the following after a software/calibration update:
| • | Idle air control (IAC) learned position |
| • | Automatic transmission shift adapts |
Other learned values only re-learn by performing a service procedure.
If a control module is replaced the following service procedures may
need to be performed:
| • | The crankshaft variation learn procedure |
| • | The engine oil life reset procedure |
| • | The idle learn procedure |
| • | The inspection/maintenance complete system set procedure |
| • | The vehicle theft deterrent password learn procedure |
| • | The throttle position (TP) sensor learn procedure |
