The following service tools should be used to aid in troubleshooting the electrical system.
Service Tools     | |
---|---|
Part Number     | Part     |
    | AVSpare Electronic Technician (ET)     |
6V-7070 9U-7330     |
Digital Multimeter     |
8T-3224     | Needle Tip Group     |
7X-1710     | Multimeter Probe Group     |
8T-8726     | Adapter Cable Assembly     |
9U-7246     | Connector Repair Kit DT     |
4C-3406     | Connector Repair Kit     |
4C-8195     | Control Service Tool (Switch Box)     |
For instructions on servicing Sure Seal connectors, see Special Instruction, SMHS7531. For instructions on servicing Deutsch connectors, see Special Instruction, SEHS9615.
Use the digital multimeter for measuring resistance or for measuring voltage. For instructions about the use of the 6V-7070 Digital Multimeter, see Special Instruction, SEHS7734. The 7X-1710 Multimeter Probe measures the voltage at the connectors without disconnecting the connectors. The probe cables are pushed into the back of the connector along the wire. The 8T-8726 Adapter Cable has a breakout with 3 pins. The adapter cable is used for measurements in the sensor circuits.
Note: Except for harness tests, using continuity testers such as the 8T-0500 Continuity Tester or voltage testers such as the 5P-7277 Voltage Tester is not recommended for today's AVSpare electrical circuits.
AVSpare Electronic Technician
Illustration 1 | g00774942 |
Connections for the Communication Adapter II and the AVSpare Electronic Technician (ET) The components that are needed in order to use the Communication Adapter II and the AVSpare Electronic Technician ( ET) in order to determine diagnostic codes are listed: (6) Cable (7) 171-4400 Communication Adapter II (8) Service diagnostic cable. (9) Current version of Cat ET software and an IBM-COMPATIBLE personal computer |
ReferenceSee Special Publication, NEHS0758, "Communications Adapter II User's Manual Contains Software".
Note: AVSpare Electronic Technician (ET) is a software program that can be used on an IBM compatible personal computer.
In order to use the Cat ET, order the following materials: Special Publication, JERD2124, "ET Single Use Program License", Special Publication, JEHP1026, "Information and Requirements Sheet", 7X-1425 Data Link Cable and the Data Subscription and Special Publication, JERD2142, "Data Subscription". The Special Publication, JEHP1026, "Information and Requirements Sheet" lists the required hardware and the features of the Cat ET.
The Cat ET is not required in order to determine the diagnostic codes and the Cat ET is not required in order to clear the diagnostic codes. However, the process of determining the diagnostic codes is easier and faster by using the Cat ET. The Cat ET can also display information on the history of a diagnostic code and the parameter status of diagnostic codes. These features allow the Cat ET to be a useful tool for troubleshooting.
The Cat ET is used to communicate to the electronic control module over the data link by connecting to the machine diagnostic connector. For more information and the locations of the connectors, see Testing and Adjusting, "Location of Electrical Components" and the Electrical System Schematic in your machine's Service Manual.
Connecting AVSpare Electronic Technician
Illustration 2 | g00647144 |
(1) Personal computer (PC) (2) 196-0055 Adapter Cable As (3) 171-4401 Communication Adapter As (4) 207-6845 Adapter Cable As |
Note: Items (2), (3), and (4) are part of the 171-4400 Communication Adapter II Gp .
Use the following procedure to connect Cat ET and the Communication Adapter II.
- Turn the keyswitch to the OFF/RESET position. If the key switch is not placed in the OFF/RESET 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 Engine Control Module (ECM), proceed to the next Test Step.
Electronic Service Tool Does not Communicate
Probable Causes
- Configuration for the communications adapter
- J1/P1 connectors for the Engine Control Module (ECM)
- 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
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 communication adapter's power light will not be on. Proceed to Test Step 2 if the power light is not illuminated. Turn the key off in order to shut down the Cat ET if the communication adapter is powered but is still not communicating.
2. Communication Adapter and/or Cables
Ensure that all of the connections are tight and dry. If you are using a 171-4401 Communication Adapter Assembly, ensure that the firmware and the software files for the adapter are the most current that are 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
In order to eliminate Cat ET and the related hardware as the problem, connect Cat ET to a different machine. If the same problem occurs on a different machine, check Cat ET and the related hardware in order 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/P1 ECM Connectors
Check the J1/P1 ECM connectors for the following problems:
- Proper torque
- Cleanliness of the terminals
- Wires and terminals are properly installed into the connector.
Refer to Testing and Adjusting, "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 in the ON position.
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:
1. Turn the key switch to the OFF position.
2. Disconnect Cat ET.
3. Turn the key switch to the ON position.
4. Connect Cat ET.
7. 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.