3FWB01091-0 Tohatsu CYLINDER HEAD

Table 1
Diagnostic Codes Table
Code Conditions which Generate this Code System Response
591-12 EEPROM checksum fault or ECM not programmed The Integrated Combustion Sensing Module (ICSM) detects a problem within the EPROM circuit. The shutdown output is activated. The code is logged.
The ICSM may not function. If the ICSM does not function, the engine is shut down.
Table 2
Diagnostic Codes Table
Code Conditions which Generate this Code System Response
253-2 Personality Module : Erratic, Intermittent, or Incorrect The software in the right side ICSM does not match the software in the left side ICSM. The shutdown output is activated. The code is logged.
The engine is shut down.
591-12 EEPROM checksum fault or ECM not programmed An ICSM detects a problem within the EPROM circuit. The shutdown output is activated. The code is logged.
An ICSM may not function. If an ICSM does not function, the engine is shut down. Note: The ICSM contains no moving parts. Failure of the ICSM is unlikely. Before you replace an ICSM, load the flash file for the ICSM in order to be sure that the flash file is not the problem.Use the following guidelines to verify that the suspect ICSM is the cause of the problem:Install a test ICSM in place of the suspect ICSM. Transfer the software from the suspect ICSM to the test ICSM. Program all the parameters for the test ICSM in order to match the parameters of the suspect ICSM. The parameters must match. Refer to the following steps for details on programming the parameters.If the test ICSM resolves the problem, reconnect the suspect ICSM. Verify that the problem recurs. If the problem recurs, replace the suspect ICSM with the test ICSM.Use the following procedure to replace the ICSM:Note: If the parameters cannot be read from the suspect ICSM, the parameters must be obtained from records or from the factory.
Use the "Service/Copy Configuration/ECM Replacement" function of Caterpillar Electronic Technician (ET) in order to transfer the software from the suspect ICSM. You may also select the "Print" function in order to obtain a paper copy of the parameter settings.Note: Before you replace an ICSM, record all of the logged events.
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.
Select "Load from ECM" in the lower left corner of the screen. Select the suspect ICSM 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".
Select "File/Disconnect F8" from the pull-down menu. Note: Do not exit from Cat ET.
Replace the ICSM.
Turn the engine control switch to the "OFF/RESET" position.
Illustration 1 g00842289
16 amp circuit breaker for the ECM
Switch the 16 amp circuit breaker for the ECM to the OFF position.
Illustration 2 g00842252
(1) 20 pin connector for the thermocouples
(2) 14 pinconnector to the terminal box
(3) Bolt
Disconnect the 20 pin connector (1) and the 14 pin connector (2) from the ICSM. Remove four bolts (3) in order to remove the cover. Note: Rubber grommets for the ICSM are held in place on the mounting studs. The grommets help to reduce vibration. The grommets may fall when the ICSM is removed. Be sure not to lose the grommets.Note: A ground strap is connected with one of the mounting bolts.
Illustration 3 g00842267
(4) Connectors for the sensors
(5) Mounting bolts
(6) Ground strap
Disconnect connectors (4) for the sensors from the ICSM. Remove four mounting bolts (5). Detach ground strap (6).
Install the replacement ICSM. Orient the 20 pin connector to the upward position.
Use the mounting hardware to install the new ICSM. Be sure to install ground strap (6). Check the mounting hardware and the ICSM for correct installation. A properly installed ICSM will move slightly on the rubber grommets. If the ICSM cannot move slightly on the grommets, check that the washers and grommets are positioned correctly.
Connect connectors (4) for the sensors to the ICSM.
Connect the 20 pin connector (1) and the 14 pin connector (2) to the ICSM.
Install the cover and four bolts (3).
Program the configuration parameters and the monitoring system parameters into the replacement ICSM.
Switch the 16 amp circuit breaker for the ECM ON.
Turn the engine control switch to the "STOP" position.
Select "File/Select ECM" from the pull-down menu of Cat ET.
Select the "Replacement ICSM" and click "OK".
Select "Service/Copy Configuration/ECM Replacement" from the pull-down menu. Click "OK" on the window.
Select "Program ECM" from the lower left corner of the screen. Select the replacement ICSM and click "OK".
After the loading is complete, a window with the message "Programming Complete" will appear. Select "OK". Note: When you program a new ICSM, factory passwords are not required. Also, the ICSM does not require calibration.