FLANGE 4Y7477 - Caterpillar

Illustration 1 g01620793
Schematic of the "Transmission Clutch (Solenoid 3)"
Note: The approximate coil resistance of the solenoid is 8.7 .4 ohms at 25 °C (77.0 °F).This diagnostic code is recorded when the ECM reads the current of the solenoid circuit as being below normal range (open circuit).Note: This procedure can cause new diagnostic codes to be recorded. Ignore these created diagnostic codes. Complete the following procedure. Then clear the created diagnostic codes.Test Step 1. CHECK THE SOLENOID.
Turn the disconnect switch and the key start switch to the ON position. Do not start the engine. Ensure that the diagnostic code for the solenoid is active.
Disconnect the machine harness from the solenoid.
At the machine harness connector for the solenoid that is being tested, install a jumper wire. Install the jumper wire from contact 1 (wire 754-BU(Blue)) to contact 2 (wire 922-BR(Brown)).
Observe the status of the diagnostic code. The diagnostic code is active or the diagnostic code is NOT active. Expected Result:The status of the diagnostic code is active and the status of the diagnostic code is NOT active as the jumper wire is installed and then removed.Results:
YES - The circuit is correct. The solenoid has failed.Repair: Repeat this test "CHECK THE SOLENOID" in order to verify the solenoid failure. Replace the solenoid.STOP
NO - The diagnostic code remains active. Proceed to test step 2.Test Step 2. CHECK THE SOLENOID CIRCUIT FOR AN OPEN.
The jumper wire that is between the signal wire and the return wire remains installed.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness connector J1 and J2from the ECM.
At the machine harness connectors for the ECM, measure the resistance from contact J1-59 for the solenoid to contact J1-60 (return contact). Expected Result:The resistance that is measured is less than 5 ohms.Results:
YES - The machine harness is correct. Proceed to test step 3.
NO - There is an open circuit in the machine harness. The open circuit is in the signal wire (754-BU(Blue)) or in return wire (922-BR(Brown)) of the machine harness.Repair: Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK IF THE DIAGNOSTIC CODE REMAINS.
Inspect the contacts of the harness connectors. Clean the contacts of the harness connectors.
Reconnect all harness connectors.
Turn the disconnect switch and the key start switch to the ON position.
Clear all of the inactive diagnostic codes.
Stop the machine. Then place the parking brake switch in the ON position.
Observe the status of the diagnostic code. The diagnostic code is present or the diagnostic code is NOT present. Expected Result:The diagnostic code for the relay is NO longer present.Results:
YES - The diagnostic code is NOT present.Repair: The diagnostic code does not exist at this time. The initial diagnostic code was probably caused by a poor electrical connection and/or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation. STOP
NO - The diagnostic code has not been corrected. It is unlikely that the ECM has failed.Repair: Exit this procedure and perform this diagnostic code