Cat® Electronic Technician (ET) is used to load the injector trim codes into the Electronic Control Module (ECM).
The injector trim codes must be loaded into the ECM if any of the following conditions occur:
- An injector is replaced.
- The ECM is replaced.
- "Injector Trim" is displayed below a 268-2 diagnostic code on Cat ET.
- Injectors are exchanged between cylinders.
Exchanging Injectors
Exchanging injectors can help determine if a combustion problem is in the injector or in the cylinder. If two injectors that are currently installed in the engine are exchanged between cylinders, the injector trim codes must also be exchanged between cylinders. Press the "Exchange" button at the bottom of the "Injector Trim Calibration" screen on Cat ET. Select the two injectors that will be exchanged and press the "OK" button. The tattletale for the injectors that were exchanged will increase by one.
- Record the injector serial number and the injector confirmation code for each injector.
- Click on "Service Software Files" in SIS Web.
- Enter the serial number for the injector in the search field.
- Download the injector trim code to the PC. Repeat this procedure for each injector, as required.
- Connect Cat ET to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools".
- Select the following menu options on Cat ET:
- Service
- Calibrations
- Injector Trim Calibration
- Select the appropriate cylinder.
- Click on the "Change" button.
- Select the appropriate injector trim code from the PC.
- Click on the "Open" button.
- If you are prompted by Cat ET, enter the injector confirmation code into the field.
- Click on the "OK" button.
The injector trim code is loaded into the ECM.
- Repeat the procedure for each cylinder, as required. If the download of the injector trim code fails, confirm that the part number for the injector is correct. Repeat the previous test steps.
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Illustration 1 | g03720672 |
Typical example of the locations of the numbers on a Mechanical Electronic Unit Injector (MEUI) (1) Serial number location (2) Injector trim code location (3) Part number location |
Note: The injector serial number and the injector confirmation code are located on the injector. Cat ET may require the entry of injector confirmation code during this process. Cat ET will prompt you for the code, if necessary.