SEAL A. 7B2161 - Caterpillar

Illustration 1 g03856801
Schematic of the transmission input speed sensor
This diagnostic code is associated with the transmission input speed sensor. This diagnostic code is recorded when the ECM reads the signal from the sensor and the ECM determines that the signal is erratic, intermittent, or incorrect.The possible causes of this diagnostic code are listed:
Wire (L911-YL(Yellow)) is shorted to the ground circuit while the machine is in operation.
Wire (L910-PK(Pink)) is shorted to the +battery.
An open circuit exists.
The ECM has failed. This is unlikely.Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0669 FMI 02 is active before performing this procedure.Note: Use a digital multimeter for the measurements in this procedure.Test Step 1. VERIFY THE SOFTWARE VERSION
Verify that the latest software version has been loaded to the Chassis ECM. Expected Result:All of the software is current.Results:
OK - All of the software is current. Proceed to Test Step 2.
NOT OK - There is a more recent release of the software.Repair: Flash all controls with the latest software release. Refer to Testing and Adjusting, "Electronic Control Module (ECM) - Flash Program".STOPTest Step 2. CHECK THE HARNESS.
Turn the key start switch to the OFF position.
Inspect the harness.
Check for the proper mating.
Check the exposed wires for nicks and abrasions.
Check for moisture, dirt, or corrosion.
Check the pin/socket for a proper fit.
Disconnect the machine harness connectors from the Chassis ECM.
At the machine harness connector, measure the resistance from connector contact 2 to J1-5 (wire L910-PK(Pink)) of the Chassis ECM. Expected Result:The resistance should be less than 5 ohms.Results:
OK - The resistance is less than 5 ohms. The machine harness is correct. Proceed to test step 3.
NOT OK - The resistance is greater than 5 ohms. There is an open in the machine harness. The open is between the modules for the signal (wire L911-YL(Yellow)).Repair: Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK IF THE DIAGNOSTIC CODE IS STILL ACTIVE.
Inspect the harness connectors. Clean the contacts of the harness connectors and check the wires for damage to the insulation that is caused by excessive heat, battery acid, or chafing.
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the circuit.
Reconnect all harness connectors in order to make sure that the connectors are fully seated. Also, make sure that the clips for each connector are completely fastened.
Turn the disconnect switch and the key start switch to the ON position.
Operate the machine.
Determine if the CID 0669 FMI 02 is active. Expected Result:The CID 0669 FMI 02 is active.Results:
YES - The CID 0669 FMI 02 is active. The problem has not been corrected.Repair: Check the circuit again. If the Caterpillar Electronic Technician (ET) is available, use the Cat ET service tool in order to perform a “Wiggle Test” on the machine wiring harness. The “Wiggle Test” can detect shorts and opens in the machine wiring