Using the Operator Monitor to Determine Diagnostic Trouble Codes
Monitoring System Display
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Illustration 1 | g03720148 |
Typical Display |
The monitoring system display can display events and codes. The codes and events are reported by an ECM.
For information regarding the Monitoring System Display refer to the Operation and Maintenance Manual for your machine.
ReferenceFor the D5R2 refer to Operation and Maintenance Manual, SEBU9258, "Monitoring System" for further information.
Reference For the D6R2 refer to Operation and Maintenance Manual, SEBU9246, "Monitoring System" for further information.
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Illustration 2 | g03720513 |
The monitoring functions can show different content in the LCD. The LCD display is described below:
- There are four display modes: Machine Work Hours, Digital Battery Voltage, Engine Speed, Diagnostic, and Event ID scrolling.
- After the machine is turned ON.
- The Machine Work Hours mode is displayed
- The operator can change the modes including Machine Work Hours, Digital Battery voltage by depressing the mode switch for approximately 2 seconds and the releasing the switch.
- If there is an active diagnostic or event code, the diagnostic and event ID scrolling screen is displayed.
For an active diagnostic, the LCD displays: the MID first, followed by the CID-FMI, WCI. For active events, the LCD displays the EID-MID (WCI).
The upper right corner of the display shows the current diagnostic and event number and the total sum of diagnostic and event ID's.
Every diagnostic or event code appears automatically and each lasts for approximately 5 seconds.
Default monitoring functions are activated using the Operator switch in the cab.
Using AVSpare® Electronic Technician (Cat ET) to Determine Diagnostic Trouble Codes
Connect the AVSpare® Electronic Technician (Cat ET) to the vehicle. Turn the key switch to the RUN position. Start the Cat ET program. Cat ET will initiate communications with the Electronic Control Units on the vehicle. After communication has been established, Cat ET will list the Electronic Control modules. Choose the desired Electronic Control module. After the diagnostic trouble codes have been determined with the Cat ET, see the test procedure for the corresponding diagnostic trouble code.
ReferenceTroubleshooting, "Service Tools"
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Illustration 3 | g03829269 |
Connections for the Communication Adapter 3 Gp and Cat ET (1) Current version of Cat ET software (2) 457-6114 Communication Adapter 3 Gp (3) Service diagnostic cable (4) Cable |
Cat Electronic Technician is software that is used to access, monitor and sometimes change the data that an ECM uses to control a machine system. The service technician can use the Cat ET to perform maintenance on the machine. Some of the options that are available with the AVSpare Electronic Technician are listed below:
- Viewing the active event codes and logged event codes
- View the status of parameters.
- Clear logged diagnostic codes
- Perform calibrations of machine systems.
- Program the ECM (Flash) using the "WINflash" program. See Troubleshooting, "ECM - Software Install".
- Print reports.
The following list contains some of the diagnostic functions and programming functions that are performed by the service tools.
- The failures of the ECM system are displayed.
- The status of most of the inputs and the outputs are displayed.
- The settings for the ECM are displayed.
- Display the status of the input and output parameters in real time.
- Display the clock hour of the internal diagnostic clock.
- The number of occurrences and the clock hour of the first occurrence and the last occurrence is displayed for each logged diagnostic code.
- The definition for each logged diagnostic code and each event is displayed.
- Load new FLASH software.
See Troubleshooting, "Diagnostic Code List" for the list of diagnostic codes for the ECM.
- Active diagnostic codes
- Logged diagnostic codes
Connecting Cat ET and the Communication Adapter III
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Illustration 4 | g03720609 |
Use the following procedure to connect Cat ET and the Communication Adapter III.
- Turn the keyswitch to the OFF position. If the key switch is not placed in the OFF position, the engine may start.
- Connect cable (2) between the "COMPUTER" end of communication adapter (3) and the RS232 serial port of PC (1) .
- Connect cable (4) between the "DATA LINK" end of communication adapter (3) and the service tool connector.
- Turn the keyswitch to the ON position. If Cat ET and the communication adapter do not communicate with the other ECM modules, proceed to the next Test Step.
Active Diagnostic Codes
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Illustration 5 | g03720680 |
Typical Cat ET screen for Active Diagnostic codes |
The following procedures may cause new diagnostic codes to be logged. Therefore, before any procedures are performed, make a list of all the active diagnostic codes to determine the system problems. Clear the diagnostic codes that were caused by the procedure, when each procedure is complete.
Note: Before performing a procedure, always check all the circuit breakers. Repair the cause of any circuit breaker that is tripped.
A screen is provided in Cat ET for active diagnostic codes. The screen will display the diagnostic codes that are active. Active diagnostic information shall include a component identifier (CID), a failure mode identifier (FMI) and a text description of the problem.
Logged Diagnostic Codes
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Illustration 6 | g03720698 |
Typical Cat ET screen for Logged Diagnostic codes |
A screen is provided in Cat ET for logged diagnostic codes. The screen will display diagnostic codes that are logged. The Cat ET will log diagnostic codes that are intermittent. The logged diagnostic data shall include a component identifier (CID), a failure mode identifier (FMI), and a text description of the problem. Also, the logged diagnostic data shall include the number of occurrences of the problem and two time stamps. The time stamp displays the first occurrence of the problem and the time stamp displays the most recent occurrence of the problem.
Diagnostics are logged in non-volatile memory. On powerup, the ECM will clear any diagnostic codes that have not been detected or active within the last 150 hours of machine operation.
Electronic Service Tool Will not Communicate with ECM
Probable Causes
- Configuration for the communications adapter
- J1 connectors for the other control modules
- Communication adapter and/or cables
- Electrical power supply to the service tool connector
- AVSpare Electronic Technician (ET) and related hardware
- Electrical power supply to the ECM
- Override switches
- J1939 Data Link and CDL Data Link
Recommended Actions:
1. Electrical Power Supply to the Service Tool Connector
Verify that the battery voltage is present between terminal A and terminal B of the service tool connector. If the communication adapter is not receiving power, the power light for the communication adapter will not be on. Proceed to Test Step 2 if the power light is not illuminated. Try turning the key off and shutting down Cat ET if the communication adapter is powered but is still not communicating.
2. Communication Adapter and/or Cables
Insure all of the connections are tight and dry. If you are using a 171-4401 Communication Adapter Assembly, ensure that the firmware and software files for the adapter are the most current available. If the firmware and the software do not match, the communication adapter will not communicate with Cat ET. Proceed to Test Step 3.
3. Cat ET and Related Hardware
To eliminate Cat ET and the related hardware as the problem, connect Cat ET to a different engine. If the same problem occurs on a different engine, check Cat ET and the related hardware to determine the cause of the problem. If Cat ET and the hardware are good, proceed to Test Step 4. If you cannot gain communications on another machine, proceed to Test Step 8.
4. J1 ECM Connectors
Check the J1 ECM connectors for the following problems:
- Proper torque
- Cleanliness of the terminals
- Wires and terminals are properly installed into the connector.
ReferenceRefer to Troubleshooting, "Electrical Connectors - Inspect" for additional information.
Proceed to Test Step 5.
5. Electrical Power Supply to the ECM
If the ECM is not receiving battery voltage, the ECM will not communicate. Check the electrical power to the ECM. Proceed to Test Step 6 if there is no power to the ECM.
6. Override Switches
Verify that there are no aftermarket devices that are preventing battery voltage from reaching the ECM. Some type of override switch is interrupting the power to the ECM if the following conditions are true:
- Communication occurs when the engine is running
- No communication occurs when the engine is not running and the key switch is ON
Try starting the engine and gaining communications. This procedure may solve the communication problem. If the problem is not fixed, proceed to Test Step 7.
Perform the following procedure:
a. Turn the key switch to the OFF position.
b. Disconnect Cat ET.
c. Turn the key switch to the ON position.
d. Connect Cat ET.
7. J1939 Data Link and CDL Data Link
Troubleshoot the J1939 Data Link and CDL Data Link for possible problems.
ReferenceRefer to Troubleshooting, "CAN Data Link - Test".
8. Configuration for the Communications Adapter
1. Access "Preferences" under the "Utilities" menu on Cat ET.
2. Verify that the correct "Communications Interface Device" is selected.
3. Verify that the correct "Port" is selected for use by the communication adapter. The most commonly used port is "COM 1".
4. Check for any hardware that is utilizing the same port as the communications adapter. If any devices are configured to use the same port, exit or close the software programs for that device.