This article mainly introduces CATERPILLAR 3406E, C-10, C-12, C-15, C-16 AND C-18 TRUCK ENGINEECM Will Not Accept Factory Passwords

Caterpillar 18 Digits Factory Password Calculator One-Time Calculate Service

Probable Causes

The probable root causes are listed in order below:

Incorrect password

Incorrect Serial Number

Incorrect reason code

Error on Entered Information

Recommended Actions

Perform the following diagnostic procedures in order:
1. Verify that the electronic service tool is on the factory password screen. Also, verify that the electronic service tool expects factory passwords rather than customer passwords.

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2. Verify the following information:

a. Verify that the Engine Serial Number that is used to calculate the password is from the electronic service tool screen rather than the engine information plate.
For example, the Engine Serial Number that is programmed in a new ECM is XXX00000.

If the Electronic Service Tool indicates that the Engine Serial Number is XXX00000, this Engine Serial Number must be used to obtain factory passwords. DO NOT use the information on the engine information plate.b. Verify that all of the information on the electronic service tool is the information that was supplied to Caterpillar in order to obtain the password.

c. Verify that the information was obtained from the ÉCM that is being programmed. DO NOT accept the information from the old ECM in order to program factory passwords on a replacement ECM . DO NOT copy the information from the old ECM in order to program factory passwords on a replacement ECM.

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d. Verify that all characters in the ECM and/or the electronic service tool serial number have been supplied.

3. Verify that the correct passwords were entered in the upper case only. Also check the characters in the password for accuracy.

4. Turn the key switch to the OFF position and retry.
Note: Ensure that the recorded information that is used to request the password is an exact match to the information that is displayed on the electronic service tool.

5. If rechecking the passwords does not correct the problem, change a customer parameter from the current value to another value and then change the customer parameter back to the original value. Then revert to the screen and proceed to obtain factory passwords again.
Note: Changing a parameter with the above method changes the Total Tattletale. The new Tattletale will require obtaining a new password.

6. Verify that the correct reason code from the factory password screen was entered. Do not assume the reason code. This must be obtained from the electronic service tool. Reason codes are assigned for specific purposes and reason codes are not interchangeable.

7. Turn the key switch to the OFF position and retry.
Note: Ensure that the information that is entered is an exact match to the information that is displayed on the electronic service tool.