G3520B Engines Caterpillar

The Integrated Temperature Sensing Module (ITSM) contains no moving parts. Replacement of the ITSM can consume much time. Before you replace an ITSM, follow the troubleshooting procedures in this manual in order to be sure that replacement of the ITSM will correct the problem.

Use the following guidelines to verify that the suspect ITSM is the cause of the problem:

Install a test ITSM in place of the suspect ITSM. Transfer the software from the suspect ITSM to the test ITSM. Program all the parameters for the test ITSM in order to match the parameters of the suspect ITSM. The parameters must match. Refer to the following steps for details on programming the parameters.

If the test ITSM resolves the problem, reconnect the suspect ITSM. Verify that the problem recurs. If the problem recurs, replace the suspect ITSM with the test ITSM.

Use the following procedure to replace the ITSM:

Note: If the parameters cannot be read from the suspect ITSM, the parameters must be obtained from records or from the factory.

1. Use the "Service/Copy Configuration/ECM Replacement" function of the Caterpillar Electronic Technician (ET) in order to transfer the software from the suspect ITSM.

   You may also select the "Print" function in order to obtain a paper copy of the parameter settings.

   Note: Before you replace an ITSM, record all of the logged events.

   1. Connect Cat ET with the communications adapter. Select "Service/Copy Configuration/ECM Replacement" from the pull-down menu.

      Cat ET will load the configuration parameters and the monitoring parameters from the ECM.

   2. Select "Load from ECM" in the lower left corner of the screen. Select the suspect ITSM and select "OK".

      After the loading is complete, Cat ET will display this message: "The data has been successfully loaded from the ECM". Select "OK".

   3. Select "File/Disconnect F8" from the pull-down menu.

      Note: Do not exit from Cat ET.

2. Replace the ITSM.

   1. Set the engine control to the OFF/RESET mode.
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   Illustration 1	g00887190
   Terminal box for the master ECM (1) 16 amp circuit breaker

   2. Switch 16 amp circuit breaker (1) to the OFF position.
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   Illustration 2	g00905364
   Connectors for the ITSM (2) Connectors for the harness to the terminal box for the master ECM (3) Connectors for the harness to the thermocouples

   3. Disconnect connectors (2) and (3) from the ITSM.
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   Illustration 3	g00743195
   Mounting hardware for the ITSM (4) Nut (5) Washer (6) Mounting flange on the ITSM (7) Rubber grommet (8) Washer (9) Ground strap

   Note: One of the mounts for the ITSM has a ground strap that is attached between the nut and the washer.

   4. Remove the 4 mounting nuts (4) and washers (5) from mounting flanges (6) of the ITSM. Ground strap (9) must also be detached from one of the studs.

   Note: Rubber grommets for the ITSM are held in place on the mounting studs. The grommets help to reduce vibration. The grommets may fall when the ITSM is removed. Be sure not to lose the grommets.

   5. Remove the ITSM from the engine.

3. Install the replacement ITSM. Orient the 54-pin connector toward the right of the engine.

   1. Use the mounting hardware to install the new ITSM. If all of the hardware has been removed, lubricate the bottom washers between the mounting plate and the rubber grommets. Be sure to install ground strap (9) between one of the washers on the mounting flange and the nut.

      Note: One of the washers is a lock washer. Be sure to install the lock washer between nut (4) and mounting flange (6). The lock washer improves the electrical conductivity between the ground strap and the mounting flange.

      Check the mounting hardware and the ITSM for correct installation. A properly installed ITSM will move slightly on the rubber grommets. If the ITSM cannot move slightly on the grommets, check that the washers and grommets are positioned correctly.

   2. Connect connectors (2) and (3) to the ITSM.

4. Program the configuration parameters and the monitoring system parameters into the replacement ITSM.

   1. Switch the circuit breaker in the terminal box ON.

   2. Set the engine control to the STOP mode.

   3. Select "File/Select ECM" from the pull-down menu of Cat ET.

   4. Select the "Replacement ITSM" and click "OK".

   5. Select "Service/Copy Configuration/ECM Replacement" from the pull-down menu. Click "OK" on the window.

   6. Select "Program ECM" from the lower left corner of the screen. Select the replacement ITSM and click "OK".

   7. After the loading is complete, a window with the message "Programming Complete" will appear. Select "OK".

      Note: When you program a new ITSM, factory passwords are not required. Also, the ITSM does not require calibration.