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 2 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 |
All 4 methods may not be availabe for every vehicle.
For information on programming a control module using one of the methods listed
above, refer to
Service Programming System (SPS)
.
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 |