Before Programming a Control Module
Important: Do NOT program a control module unless you are directed by a service
procedure or you are directed by a General Motors Corporation service bulletin.
Programming a control module at any other time will not permanently correct
a customers concern.
Ensure the following conditions are met before programming a control
module:
| - | There is no charging system concern. All charging system concerns
must be repaired before programming a control module. |
| - | Battery voltage is greater than 12 volts but less than
16 volts. The battery must be charged before programming the control
module if the battery voltage is low. |
| - | A battery charger is NOT connected to the vehicle's 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 vehicle's
battery. |
| • | Daytime running lights (DRL) |
| • | Applying the parking brake, on most vehicles, disables the DRL system.
Refer to the Owner's Manual. |
| • | Auxiliary coolant pumps |
| • | Radio, cassette or CD player |
| • | The ignition switch is in the proper position. The Techline®
terminal 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 is secure. |
| - | Voltage supply circuits |
Notice: DO NOT disturb the tool harness while programming. If an interruption
occurs during the programming procedure, programming failure or control module
damage may occur.
Programming the ECM
Important: The ECM can only be programmed using the Pass-Thru Programming method.
The Pass-Thru Programming method requires the use of a scan tool in series
with the Techline® Terminal and the DLC.
- Turn OFF the ignition.
- From the Techline® terminal, select Service Programming System.
- Select Pass-Thru as the Diagnostic Tool.
- Select the Programming Process you are using.
- Select Vehicle for the ECU location.
- Complete the vehicle information on the Connect Scan Tool/Determine
Vehicle screen.
- Turn ON the ignition with the engine OFF.
- Install the Tech 2® to the data link connector (DLC).
- Connect the RS-232 cable to the Tech 2® and the Techline
terminal.
- Turn ON the Tech 2® and wait for the Start screen.
- Verify the displayed VIN on the Techline® terminal with the
vehicle VIN. Correct the VIN as necessary.
- Select the type of module you are programming.
- Select the type of programming that you are performing.
- Select the appropriate calibration file.
Important: DO NOT turn OFF the ignition if the programming procedure is interrupted
or unsuccessful. Ensure that all the ECM and DLC connections are secure and
the Techline® operating software is up to date. Attempt to reprogram
the control module. If the control module cannot be programmed, replace the
control module. Refer to
Engine Control Module Replacement/Programming
.
- Verify the Current calibration with the Selected calibration then select
Next. This will initiate the download of the calibration files.
- After the download is complete, EXIT Service Programming.
- Turn OFF the ignition for 30 seconds.
- If the control module was replaced, the following procedures must
be performed:
Programming Verification
- With a scan tool, clear the DTCs.
- Attempt to start the engine.
- Repeat the Service Programming procedure if the engine does not
start or operates poorly. Perform the following procedures before programming
the ECM.
| • | Ensure the control module and DLC connections are OK. |
| • | Ensure the Techline® operating software is up to date. |
| • | Ensure the calibration part number is correct for the vehicle. |
- Attempt to program the control module. If the control module still
cannot be programmed properly, replace the control module. Refer to
Engine Control Module Replacement/Programming
.
