MSS3s Machine Security System Caterpillar

The machine security system (MSS) is designed to restrict operation of a machine. A list of the authorized electronic keys for a machine is contained in the electronic control module (ECM) for the MSS. Only a Cat ^® electronic key that is authorized can disarm the MSS. Disarming is accomplished by assigning the ID of an electronic key to the ECM for the MSS. The Cat ^® Electronic Technician (Cat ^® ET) service tool must be used to program the ECM with the authorized keys.

When the exciter coil is used with MSS, the electronic key is placed in the keyswitch of the machine and turned to the ON position. The ECM will read the unique ID that is stored in the key. The ECM will then compare this ID to the list of authorized keys.

If the ID of the key that is read matches an authorized key, the following actions will occur:

• The status indicator will turn a green color.

• The MSS will disarm allowing the machine to operate.

If the ID of the key that is read does not match the list in the ECM, the following actions will occur:

• The status indicator will become a red color.

• The MSS remains in the armed state.

• The machine will remain disabled.

Note: Ensure that you have only one electronic key near the exciter coil when the MSS reads the key. If more than one electronic key is near the exciter coil, the MSS3s ECM will not read the key and the machine will not start.

The machine security system can be installed in a combination of ways:

1. Electronic Control

   The MSS disables the machine by controlling up to two devices (relays) that are used to power a critical machine system.

2. Immobilizer

   The MSS disables the machine by communicating with other electronic control modules across the J1939 CAN Data-Link and Cat ^® Data- Link (CDL) by disabling critical machine functions.

To change the list of authorized keys or configuration parameters, the user must have one of the following items:

• Cat ^® Electronic Technician (Cat ^® ET) service tool and a key with master access level for that specific machine security system

• Cat ^® ET and a factory password

When a key with the master access level is not available, a factory password is required to change certain parameters in the configuration.

Refer to Testing and Adjusting, "Factory Password - Obtain" for additional information on factory passwords.

The Cat ^® ET screen for the factory level security password will display the following parameters:

• ECM serial number

• Product ID (Serial number of the machine)

• Serial number of the service tool

• Reason code

• Total tattletale number

To obtain the proper passwords, the information must be given to an authorized Cat ^® dealer.

If a key with the master access level for the machine is not available, a factory password must be entered before changes can be made. The following information is needed before you call for a factory password:

Table 1

Information That is Needed for the Factory Password
Product Identification
Software Part Number from MSS3s ECM
Serial Number from ET
Tattletale
Reason Code	99 or 4

Note: The password may only be used for one programming session. A different password will be required after you exit the Cat ^® ET screen.