3126B TRUCK ENGINE FOR FMTV MILITARY AP Caterpillar

The Caterpillar Electronic Service Tools are designed to help the service technician analyze and locate faults or problems within the system. They are required to perform calibrations, and to read or change engine parameters.

Caterpillar ET (Electronic Technician) is a software program that runs on a personal computer and requires a Caterpillar Communication Adapter or MPSI Pro-Link with Caterpillar Cartridge to translate information from the ATA Data Link to the computer RS-232 port. Caterpillar ET is the recommended Service Tool.

ET (Electronic Technician) can be used to display the following information:

* Programmble Parameter Settings

* Active and Logged Diagnostic Codes

* Logged Events

* Current Totals

* Maintenance Intervals

ET (Electronic Technician) can also be used to perform the following functions:

* Diagnostic Tests

* Sensor Calibrations

* Flash Programming

* Parameter Programming

* Copy Configuration (ECM Replacement)

* Data Logging

* Real Time Graphing

The Electronic Control Analyzer Programmer (ECAP) service tool can also be used in a limited capacity but it is no longer supported. ECAP uses small plug-in modules, called Service Program Modules (SPM), to adapt the basic tool to the specific Caterpillar electronic control application.

There are several adapter cables, breakout T cables, probes, etc, that are used in order to access measurements of signals. A heavy duty multimeter is suitable for making the necessary measurements, a multimeter that is capable of measuring Duty Cycle may also be required. Other Special Tools include those needed to measure pressure or temperature.

3126B Service Tools

Optional 3126B Service Tools

Connecting ET (Electronic Technician)

The communications Adapter is powered by 12 volts DC from the vehicle battery. This permits operation beside the engine or in the cab of a truck, to allow use during vehicle operation.

Use the following procedures to connect the service tool to the engine.

1. Turn ignition key to the OFF position.

2. The PC (with ET software installed) should be connected to the engine system through the Cab Diagnostics Connector. There are several types of cab connectors used. Determine the necessary Adapter Harness Assembly from the tool list for the vehicle you are working with. Connect the appropriate adapter to the Service Tool Harness Cable.

3. Connect the opposite end of the Service Tool Harness Cable to the Communication Adapter (refer to diagrams for specific type).

4. Connect the Communication Adapter to the PC using the appropriate cable as shown.

5. Turn ignition key to the ON position to begin testing. The Service Tool will operate with the engine running, or with the engine OFF, ignition key ON. If the Tool does not communicate with the ECM, disconnect and reconnect the Cab Diagnostic Connector cable. Check communication, if the problem is still present refer to "PB-21: SAE J1587/1708 (ATA) Data Link Circuit Test" on page 194.

NOTE: The Service Tool may restart during engine cranking due to a voltage dip on the battery line.

NOTE: ET must be configured to communicate with the specific type of Communication Adapter used. Go to the "Preferences" menu located under "Settings" to select the appropriate communications device.

Passwords

Factory Passwords

Factory passwords are required to perform each of the following five functions.

1. Program a New ECM

- When an ECM is replaced, the System Configuration Parameters must be programmed into the new ECM (if the ET ECM Replacement feature is NOT used). These parameters are protected by factory passwords.

2. Rerate Engine to Another Power Family

- This requires changing the Personality Module Code, which is protected by factory passwords. Includes changing from a standard to a multi-torque personality module.

3. Read Customer Passwords

- If the owner loses his customer passwords, he will not be able to program customer parameters. Using factory passwords, enables the ability to read customer passwords, then allows use of customer passwords to program customer parameters.

4. Clear Certain Diagnostic Codes

- Diagnostic Code 190-00 (Engine Overspeed Warning) requires factory passwords to clear once it is logged. Diagnostic Code 252-11 Incorrect Engine Software (59) also requires factory passwords. It should be cleared only if you are certain the personality module is correct for the engine.

5. Unlock a "Locked" Customer Parameter

- If a Customer Parameter has been locked out, Factory Passwords are required to either unlock the parameter or change the parameter.

Certain other diagnostic codes require customer passwords. The majority of logged diagnostic codes require no passwords to clear.

Since factory passwords contain alphabetic characters, only the ECAP or ET may perform these functions.

To obtain factory passwords, proceed as if you already had the password. At some point, if factory passwords are truly needed, the ECAP or ET will request factory passwords and provide most of the information required to obtain the passwords.

Customer Passwords

If Customer Passwords have been programmed, they are then required to change ANY customer parameter. Customer Parameters are those that affect vehicle speed limits, power rating within a family, and PTO operation. Refer to "Customer Specified Parameters" in Section P-3.0 for details on parameters that are customer programmable.

The ECAP, ET, or MPSI Pro-Link with the Caterpillar Cartridge may change Customer Parameters. To obtain customer passwords, contact the owner of the vehicle. If the owner has lost his passwords, customer passwords may be read using an ECAP or ET (factory passwords are required in order to read the customer passwords) by following these steps.

1. Use the ECAP or ET to access "Read/Change System Configuration Parameters", then "Read Customer Parameters".

2. When the Factory Passwords screen appears, record the information listed on the Factory Passwords Worksheet.

3. Obtain the factory passwords. The information recorded above must be provided, and generates a permanent record at Caterpillar of the access.

4. From the Factory Passwords screen, enter the Factory Passwords.

5. When the "Read Customer Passwords" screen appears, record the Customer Passwords. The Customer Passwords may then be used to change Customer Parameters.

Programming a New ECM

The 3126B HEUI Engine Control Module (ECM) is the heart of the system. So when a problem occurs, it is easy to jump to the conclusion that the ECM is responsible. That is usually the wrong conclusion.

Most failures occur at a sensor input/output, or in the wiring and connectors. Follow the troubleshooting procedures in this manual, and do not replace an ECM on speculation!

However, when troubleshooting indicates that a failure has occurred in the ECM, the following procedure outlines the steps required to replace a faulty ECM.

NOTE: If an ECM replacement is required, the ECM parameters and timing calibration can be transferred from the suspect ECM to the replacement ECM. Timing calibration will NOT be necessary. This feature requires Caterpillar Electronic Technician (ET) and is only possible if the existing ECM can communicate with Caterpillar Electronic Technician (ET).

Replacing The ECM Using ET ECM Replacement Feature

1. Ensure the ECM is the problem by first temporarily connecting a test ECM. Do this by hanging it on the side of the engine. Flash Program the same Personality Module from the suspect ECM to the test ECM. Program any parameters necessary to check the ECM for the test. For example, Vehicle Speed Parameters need to be programmed to check the vehicle speed circuit. Program the parameters exactly the same as they were in the suspect ECM. Check out the new ECM. If it repairs the problem, reconnect the old ECM using the same Personality Module as the test ECM. Recheck the old ECM to verify the problem stays with the ECM.

2. Select the ET ECM Replacement feature under the Copy Configuration Menu to record parameters from the failed ECM.

3. Replace the faulty ECM, temporarily connect the new one by connecting both ECM Connectors. Do not mount the ECM on the engine yet.

4. Flash program the Personality Module into the new ECM (if not already installed). The new ECM is shipped with a blank Personality Module.

5. Use the ET ECM Replacement feature to program the new ECM.

6. Enter the Rating Number parameter into the new ECM.

7. Check for Active Codes. Program any parameters requiring programming that have not been programmed.

NOTE: On initial power-up of a new ECM, the Rating Number parameter must be programmed to avoid a 253-02 Check Customer Or System Parameters (56) Diagnostic Code.

8. If a 22-13 Check Timing Calibration Diagnostic Code is not Active, install the new ECM on the engine. If the code is Active, perform a Timing Calibration first.

Replacing The ECM (If ET ECM Replacement Feature Cannot Be Used)

1. Ensure the test ECM is the problem by first temporarily installing the test ECM. Do this by hanging it on the side of the engine. Flash Program the same Personality Module from the suspect ECM to the test ECM. Program any parameters necessary to check the ECM for the test. For example, Vehicle Speed Parameters need to be programmed to check the vehicle speed circuit. Program the parameters exactly the same as they were in the suspect ECM. Check out the test ECM. If it repairs the problem, reconnect the old ECM using the same Personality Module as the test ECM. Recheck the old ECM to verify the problem stays with the ECM.

2. Record customer parameters from the failed ECM.

- Obtain and record the Customer Passwords. If the customer (owner) has lost or forgotten the passwords, proceed to Customer Passwords on page 23 for more details.

- Use the ECAP or ET to access Read Customer Specified Parameters from the ECM being replaced.

- Use the Customer Parameter Worksheet on page 27 to record the customer parameters.

3. Record ECM lifetime Totals.

- Use the Lifetime Totals Worksheet on page 29 to record the old ECM Lifetime Totals.

4. Replace the faulty ECM, temporarily connect the new one by connecting both ECM Connectors. Do not mount the ECM to the engine until the timing calibration has been performed.

5. Flash program the Personality Module into the new ECM (if not already installed). The new ECM is shipped with a blank Personality Module.

6. Obtain Factory Passwords.

NOTE: Full Load Setting (FLS), Full Torque Setting (FTS) and engine serial number can be programmed without factory passwords on a new ECM. System Configuration parameters should be entered before the Customer Specified Parameters are entered.

If Customer Parameters are entered before the System Configuration Parameters, the Total Tattletale will change. It will then be necessary to obtain another set of Factory Passwords to access Read/Change System Configuration Parameters.

- Use the Factory Passwords Worksheet on page 27 to record the following information from the Engine Information Plate: Full Load Setting, Full Torque Setting, and Engine Serial Number.

- Record the mileage from the vehicle odometer. Use the ECAP or ET to access Read/Change System Configuration Parameters. When the Factory Specified Passwords screen appears, record the following information, ECM serial number, Engine serial number, ECAP or ET serial number, Total Tattletale, and Reason Code.

- Leave the ECAP or ET on the Factory Specified Passwords screen and obtain the Factory Passwords. Fill out the Factory Passwords Worksheet on page 27.

7. Program the new ECM.

NOTE: On initial power-up of a new ECM, five parameters must be programmed to avoid a 253-02 Check Customer Or System Parameters (56) Diagnostic Code. These codes are Full Load Setting (FLS), Full Torque Setting (FTS), Vehicle Speed Calibration (ppm), Rating Number and Engine Serial Number.

- Use the ECAP or ET to access Read/Change System Configuration Parameters. Program the Truck Manufacturer parameter and enter the Full Load Setting, Full Torque Setting, and Engine serial number recorded on the worksheet.

- Use the ECAP or ET to access Read/Change Customer Specified Parameters. Enter the Customer Specified Parameters and the original Customer Passwords recorded on the worksheet.

- Use the ECAP or ET to access Read/Change Current Totals (from the Read/Change Current Totals main menu). Record information using the Factory Passwords Worksheet on page 27 to obtain the Factory Passwords. Enter the Totals recorded on the worksheet from the original ECM.

- Use the Electronic Service Tool to access Calibrate Sensors, and calibrate the Engine Speed/Timing Sensor. Refer to PC-31: Engine Speed/Timing Circuit Test on page 210.

8. Install the new ECM on the engine.

Programming a Personality Module Using Flash Programming

1. Connect the PC to the appropriate Communication Adapter and Connect the Communication Adapter to the ECM. Refer to Connecting ET (Electronic Technician) on page 22.

2. Start the ET WinFlash PC Program.

3. Ensure the Ignition Key Switch is ON, engine OFF.

4. Select the engine Personality Module part number to be programmed into the ECM, and proceed with programming the Personality Module. A new ECM is shipped with a blank Personality Module.

NOTE: The WinFlash program provides the ECM, Application, and Software part number of the selected file. Make sure this file matches the engine before you begin to Flash the file into the ECM.

5. PC Program Personality Module Messages and Their Meaning.

NOTE: A new ECM comes with a blank (previously unprogrammed) personality module. A blank personality module will prompt you for all three of the following messages. The information contained in the "ECM Status" will be scrambled and meaningless if the module has not been previously programmed (this is normal).

- Message - "The engine ID in the flash file does not match the engine ID in the ECM."

- Meaning - The ECM has a personality module for a different engine. For example, the ECM has a Basic personality module, and you are attempting to program a Full Feature personality module.

- What you should do. Stop the transfer and access information about ECM Status under the Engine Control Module menu. Ensure the file you are about to transfer is for the same engine it will be installed.

- Message- "The application ID in the flash file does not match the application ID in the ECM."

- Meaning- The ECM has a personality module for a different application. For example, the ECM has a Full Feature On-Highway Truck personality module and you are attempting to program a 3126 Marine personality module.

- What you should do. Stop the transfer and access information about ECM Status under the Engine Control Module menu. Ensure the file you are about to transfer is for the On-Highway Truck application.

- Message- "The ECM ID in the flash file does not match the ECM ID in the ECM."

- Meaning- The ECM is not for use in the 3126B HEUI On-Highway truck application.

- What you should do. Stop the transfer and access information about ECM Status under the Engine Control Module menu. Ensure the ECM on the engine is for a 3126B HEUI On-Highway truck application.

NOTE: The time it takes to flash a Personality Module is significantly longer than earlier applications. It can take 10 minutes or longer with a Caterpillar 7X-1701 Communication Adapter, and 20 minutes or longer using a MPSI Pro-Link with the Caterpillar cartridge as a communications adapter.

The 171-4401 Communication Adapter II has the ability to Flash Program using the J1939 data link. This results in much faster flash times. However, the vehicle wiring harness must have J1939 support in order to flash program using the J1939 data link. If J1939 communications are not supported, the 171-4401 Communication Adapter II will use the ATA data link for flash programming, resulting in similar flash times as the 7X-1701 Communication Adapter.

NOTE: If you access the ECM Status under the Engine Control Module menu of the PC Program, but do not follow this information access by programming the Personality Module, turn the vehicle ignition key switch to the OFF position, and then to the ON position before using an ECAP or ET. If the ignition key switch is not cycled after reading the ECM Status, the ECM will not communicate with your Service Tool, or start. Cycling the ignition key switch is not necessary following successful programming of a Personality Module using the WinFlash Program.

6. Start the engine and check for proper operation.

- Program any parameters not previously in the old personality module if 253-02 Check Customer Or System Parameters (56) Diagnostic Code is active. Read the diagnostic code from the Service Tool Active Diagnostic Code screen to determine the parameter(s) requiring programming.

- Remember, on initial power-up of a new ECM, five parameters must be programmed to avoid a 253-02 Check Customer Or System Parameters (56) Diagnostic Code, Full Load Setting (FLS), Full Torque Setting (FTS), Vehicle Speed Calibration (ppm), Rating Number and Engine Serial Number. Refer to Programming a New ECM on page 24.

Factory Passwords Worksheet

Customer Parameter Worksheet

Lifetime Totals Worksheet

Service Information Report

After verifying the correct repair has been performed on the vehicle it is critical to provide concise, detailed information. This information helps Caterpillar better serve you and the Customer.

Recommendations

Customer's Complaint

Provide a copy of the PA-10:Driver Questionnaire on page 44. Include comments for the Customer's Complaint section of the report indicating if the Check Engine Lamp was ON continuously or intermittently, if symptoms such as the truck had low power are present, indicate this.

Failure Cause

Comments on Failure Cause should include the number of diagnostic codes logged and if the code was Active. Indicate the source of the problem and how it was discovered, such as followed Procedure PC-31, or a visual inspection indicated wire abrasion on the engine harness, or truck dynamometer testing showed power below specification @ 1700 rpm and above due to loss of cylinder 4 injector. Please be specific.

How You Repaired It

Comments on How You Repaired It should include information such as repaired the wiring harness, changed FLS/FTS as per factory instructions, etc.