SHIELD-HEAT 2428826 - Caterpillar

Illustration 1 g06264595This diagnostic code is associated with the accelerator pedal position #1. The illustration for the J1939 Data Link may not represent all the connections for the components that are on machines that are covered by this manual. Refer to the electrical system schematic for your machine to verify the J1939 Data Link connections.Note: This diagnostic code is recorded when the Transmission ECM does not receive expected information from the accelerator pedal position #1 for more than 5 seconds. There is nothing wrong with the Transmission ECM. Check for active engine diagnostics.Test Step 1. VERIFY THE HARDWARE AND THE SOFTWARE PART NUMBERS.
Verify that the following information is correct:
The part number of the flash software for the Transmission ECM
The part number of the Transmission ECMNote: Consult your Caterpillar Dealer for the correct part numbers of the flash software.Expected Result:All the part numbers are correct.Results:
OK - All of the part numbers are correct. Proceed to Test Step 2.
NOT OK - All of the part numbers are not correct.Repair: The ECM has the wrong part number or the incorrect software is installed. Replace the ECM with a module that has the correct part number. Flash the correct software. See the Testing and Adjusting, "Electronic Control Module - Flash Program" section of this manual.STOPTest Step 2. INSPECT THE HARNESS CONNECTIONS.
Turn the disconnect switch to the OFF position.
Inspect all harness connections that are related to the J1939 Data Link. Make sure that the connectors are clean and tight.
Check the connectors for proper mating. Ensure that all the seals are present and in place.
Check the harness for signs of damage or abrasion.
Check the wires at the connector. Ensure that the wires are secured tightly into the connector. Take care not to pull the wire out of the connector.
Check the exposed wires at the connectors for nicks or signs of abrasion.
Check for moisture inside the connector.
Check the connectors for dirty contacts or corroded contacts.
Check each pin and each socket of the machine harness connectors. Ensure that the contacts are properly installed. The contacts should mate correctly when the two pieces of the connector are placed together.Expected Result:The machine harness connectors are tight and free of corrosion.Results:
OK - The machine harness connectors are tight and free of corrosion. Proceed to Test Step 3.
NOT OK - The machine harness connectors are in need of repair.Repair: Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK FOR SHORTS TO GROUND
The disconnect switch remains in the OFF position.
Disconnect the machine harness from all electronic control modules that use the J1939 Data Link.
At the machine harness for the Transmission ECM, measure the resistance between contacts J2-56 and J2-70 of the J1939 Data Link and frame ground.Expected Result:The resistance is greater than 5000 Ohms.Results:
OK - The resistance is greater than 5000 Ohms. The harness circuit resistance is correct. Proceed to Test Step 4.
NOT OK - The resistance is less than 5000 Ohms. The machine harness has failed.Repair: There is a short between frame ground and the J1939 Data Link