G3516 TA Engine Caterpillar

Data Link - Test

Usage:

Use this procedure to troubleshoot a problem with the data link. Also, use this procedure if one of following diagnostic codes is active or easily repeated.

Show/hide table

Table 1
J1939 Code and Description	Comments
51-9 Engine Throttle Position : Abnormal Update Rate	The ECM is not communicating properly with the throttle actuator over the CAN data link. The code is logged.
173-9 Engine Exhaust Gas Temperature : Abnormal Update Rate	The ECM is not communicating properly with the ISM over the Global CAN data link. The code is logged.
843-9 Operator Control Panel : Abnormal Update Rate	The ECM is not communicating properly with the EMCP over the CAN data link. The code is logged.
898-9 Engine Requested Speed/Speed Limit : Abnormal Update Rate	The "Desired Speed Input Configuration" must be set to "CAN" for the code to be set. The ECM is not communicating properly with the Operator Control Panel (OCP) over the CAN data link. The code is logged.
1180-9 Engine Turbocharger #1 Turbine Intake Temperature : Abnormal Update Rate	The ECM is not communicating properly with the ISM over the Global CAN data link. The code is logged.
1181-9 Engine Turbocharger #2 Turbine Intake Temperature : Abnormal Update Rate	The ECM is not communicating properly with the ISM over the Global CAN data link. The code is logged.
1442-9 Engine Fuel Valve #1 Position : Abnormal Update Rate	The ECM is not communicating properly with the fuel metering valve. The code is logged.
2241-9 Source Address 241 : Abnormal Update Rate⁽¹⁾	The ECM is not communicating properly with the ISM over the Local CAN data link. The code is logged.
3221–9 Aftertreatment #1 Intake Wide-Range O2 Reading Stable : Abnormal Update Rate	The ECM is not communicating properly with the oxygen sensor at the catalyst inlet, over the CAN data link. The code is logged.
3231–9 Aftertreatment #1 Outlet Wide-Range O2 Reading Stable : Abnormal Update Rate	The ECM is not communicating properly with the oxygen sensor at the catalyst outlet, over the CAN data link. The code is logged.
3542-9 Requested Engine Control Mode : Abnormal Update Rate	The "Engine State Control Input Configuration" must be set to "CAN" for the code to be set. The ECM is not communicating properly with the EMCP over the CAN data link. The code is logged.
3675-9 Engine Turbocharger Compressor Bypass Actuator Position : Abnormal Update Rate	The ECM is not communicating properly with the compressor bypass actuator over the CAN data link. The code is logged.
4289-9 Aftertreatment #1 Three Way Catalytic Converter Intake Gas Temperature : Abnormal Update Rate	The ECM is not communicating properly with the ISM over the Global CAN data link. The code is logged.
4290-9 Aftertreatment #1 Three Way Catalytic Converter Outlet Gas Temperature : Abnormal Update Rate	The ECM is not communicating properly with the ISM over the Global CAN data link. The code is logged.

Show/hide table

⁽¹⁾	Integrated Sensing Module (ISM) data link

If Cat^® Electronic Technician (ET) will not communicate with the ECM, refer to Troubleshooting, "Electronic Service Tool Does Not Communicate" before you begin this procedure. The procedure will verify that electrical power is being supplied to the ECM and to the service tool connector.

The data links are used to communicate information between the engine ECM and other control modules that are a part of the application. Cat ET also communicates with the ECM via the data links.

The service tool connector contains connections for electrical power and for the data links.

Cat ET may display the following error message:

"The version of the ECM is not recognized and the integrity of the changed parameters and displayed data is not guaranteed."

This message indicates one of the following conditions:

The flash file in the ECM is newer than the version of Cat ET.
The latest version of Cat ET has not been installed.

-9 Detected Problems

An invalid configuration parameter
Software incompatibility between two or more ECM's on the network
Hardware incompatibility between CAN-based system components
Damaged CAN data link wiring
Missing or damage terminating resistors

If a -9 abnormal update rate diagnostic is active for the oxygen sensor circuit, verify the 24 VDC switched power to the voltage converter is present at the voltage converter input B. If the converter is not powered by the 24 VDC switched power, the 12 VDC regulated oxygen sensor power supply will also not be enabled.

The voltage converter converts a filtered 24 VDC from the battery to 12 VDC that is used by the sensor circuit. The voltage convertor is powered and enabled by a 24 VDC switched power supply from the engine ECM. The voltage converter provides 12 VDC to each of the oxygen sensors.

Show/hide table

Table 2
Troubleshooting Test Steps	Values	Results
1. Check for Codes A. Connect Cat^® Electronic Technician (ET) to the service tool connector. B. Determine if a code is active or logged.	Codes	Result: A -9 code is active or logged. Proceed to Test Step 2.
2. Check for Battery Voltage at the Affected Component A. Turn the power to the ON position. B. Measure the voltage between the following terminals on the wiring harness connector for the affected component: - Battery (+) and Battery (-)	Battery Voltage	Result: There was battery voltage between the battery (+) and battery (-) terminals at the wiring harness connector. Proceed to Test Step 3. Result: There was not battery voltage between the battery (+) and battery (-) terminals at the wiring harness connector. There is an open or a short in the wiring harness. Repair: Repair or replace the wiring harness. Proceed to Test Step 4.
3. Check the Termination Resistors for the J1939 Data Link A. Turn the main disconnect switch to the OFF position. B. At the affected component, measure the resistance between the following CAN data link terminals: - CAN (+) and CAN (-)	60 ± 10 Ohms	Result: The resistance is less than 50 Ohms. There are more than 2 termination resistors installed in the wiring harness or a short circuit has been detected. Repair: Repair or replace damaged components. Proceed to Test Step 4. Result: The resistance is 60 ± 10 Ohms. The termination resistors are OK. Proceed to Test Step 4. Result: The resistance is approximately 120 ± 10 Ohms. There is a problem with a termination resistor or a termination resistor is missing. Repair: Check the resistance on each terminating resistor. Replace the failed termination resistor. Proceed to Test Step 4. Result: The resistance is greater than 130 ohms. There is a problem with the wiring harness between the ECM and the next connection point in the data link wiring. Repair: Repair or replace the wiring harness. Proceed to Test Step 4.
4. Check for Active CAN Communication A. Connect Cat ET. B. Use Cat ET to monitor the following: - Codes	Codes	Result: A code is not active. Return to service. Result: A -9 diagnostic is still active and communication problems continue. There may be a problem with one of the communicating devices. If multiple devices show an active-9diagnostic and the wiring is correct, you may have a problem with the ECM. If only one device is showing an active -9 diagnostic, that specific device may have a problem. Contact your dealer TC for further assistance.

If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).