For 1990-2009 cars

### Circuit/System Description

The control functions for the fuel injection system are integrated in the engine control module (ECM). Each injector's flow rate information, or injection quantity adjustment (IQA) flow rate numbers, and cylinder position are stored in the memory of the ECM. The fuel injector flow rate programming must be done when any of the following procedures are performed:

• | The ECM is replaced

• | A fuel injector is replaced

### 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:

• | Vehicle system voltage

- | There is no charging system concern. All charging system concerns must be repaired before programming a control module.

- | Battery voltage is between 12-16 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 battery. Incorrect system voltage or voltage fluctuations from a battery charger may cause programming failure or control module damage.

- | Turn OFF or disable any of the following systems that may put a load on the vehicle battery:

• | Twilight sentinel

• | Interior lights

• | Daytime running lights (DRL)--Applying the parking brake, on most vehicles, disables the DRL system. Refer to the Owner's Manual.

• | 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 of the following tool connections are secure:

- | The connection at the data link connector (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.

### ECM-IMA Diesel Injector Replacement (IQA) Programming

1. Ignition OFF.
2. Record all the IQA codes from the corresponding cylinder from each injector that is being replaced or from all injectors if the ECM was replaced.
3. From the scan main menu, select service programming system, then follow the instructions on the screen.
4. Enter the 7 digit IQA code (2) from the injector or injectors (1).

### Repair Verification

1. Install any components or connectors that have been removed or replaced during diagnosis.
2. Perform any adjustment, programming or setup procedures that are required when a component or module is removed or replaced.
3. Ignition for 60 seconds.
4. Ignition ON, engine OFF.
5. Clear the DTCs.
6. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.

OR

If the repair was symptom related, duplicate the conditions under which the customer concern occurred to verify the repair. If the customer concern reoccurs, return to Symptoms - Vehicle and perform the appropriate symptom diagnostic.