SEGMENT GP-SPROCKET 1531335 - Caterpillar

If the electronic service tool will not communicate with the ECM, refer to Troubleshooting, "Electronic Service Tool Does Not Communicate" before starting this procedure. The procedure verifies that electrical power is being supplied to the ECM and to the diagnostic connector.The data links are used to communicate information between the engine ECM and other control modules that are a part of the application. The electronic service tool also communicates with the ECM via the data links.The diagnostic connector contains connections for electrical power and for the data links.When the keyswitch is in the OFF position, the electronic service tool may communicate with the ECM. However, the communications may be disrupted and the communications may require frequent reconnection. To avoid any disruption, place the keyswitch in the ON position when the electronic service tool is being used.The electronic service tool 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 that one of the following conditions exist:
The flash file in the ECM is newer than the version of the electronic service tool.
The latest version of the electronic service tool has not been installed.
Illustration 1 g03776697
Schematic for the data-type sensors
Not all connectors are shown. Refer to the appropriate Electrical Schematic.
Complete the procedure in the order in which the steps are listed.
Table 2
Troubleshooting Test Steps Values Results
1. Check the Connectors
A. Thoroughly inspect the connectors that are associated with the data link circuits. Verify that the connectors are free of debris, free of corrosion, and securely connected.
B. Perform a 45 N (10 lb) pull test on all the wires associated with the data link circuits.
Connectors
Result: The connectors were connected correctly and did not have corrosion or moisture.
Proceed to Test Step 2.
Result: The connectors were not connected correctly or the connectors have corrosion or moisture.
Repair: Repair the connectors and/or the wiring. Replace parts, if necessary. The DCU connector is not serviceable.
Proceed to Test Step 8.
2. Check for Active or Recently Logged Diagnostic Codes
A.Establish communication between the electronic service tool and the engine Electronic Control Module (ECM). Refer to Troubleshooting, "Electronic Service Tools"
B.Download the "Warranty Report" from the engine ECM before troubleshooting or clearing diagnostic trouble codes.
C.Establish communication between the electronic service tool and the Dosing Control Unit (DCU) .
D. Look for active or logged codes.
Diagnostic Trouble Codes
Result: There is an active or recently logged 3216-11 or 3226-11 diagnostic code.
Proceed to Test Step 3.
Result: There is an active or recently logged 3216-12 diagnostic code.
Proceed to Test Step 4.
Result: There is an active or recently logged 3226-12 diagnostic code.
Proceed to Test Step 5.
Result: There is an active or recently logged 4377-12 diagnostic code.
Proceed to Test Step 6.
Result: There is an active or recently logged 3360-14 diagnostic code.
Proceed to Test Step 8.
3. Inspect the NOx Sensor
A. Remove the suspect NOx sensor.