SEAL 8T7235 - Caterpillar

Conditions Which Generate This Code:
Illustration 1 g01251022
Schematic of the transmission output speed sensor 2This diagnostic trouble code is associated with the transmission output speed sensor 2. The FMI "08" means that the ECU has determined that the signal frequency is not within the expected range. The possible causes of this diagnostic trouble code are listed below:
The sensor has failed.
Intermittent connections or poor connections
Mechanical devices are loose.
The ECU has failed. This is unlikely.Note: The following test procedure may create other diagnostic trouble codes. Ignore these created diagnostic trouble codes and clear the diagnostic trouble codes when the original diagnostic trouble code has been corrected. Ensure that the diagnostic trouble code of CID 0673 FMI 08 is active before performing this procedure. The engine must be running in order for the diagnostic trouble code to be active.Note: Use a digital multimeter for the measurements in this procedure. Test Step 1. CHECK THE SENSOR.
Turn the disconnect switch and the key start switch to the ON position.
Ensure that the diagnostic trouble code is active.
Disconnect the sensor from the machine harness.Expected Result:The diagnostic trouble code is NO longer active.Results:
OK - The diagnostic trouble code is NO longer active. The sensor has failed. Repair: Replace the sensor. Verify that the new sensor corrected this diagnostic trouble code. The diagnostic trouble code is NOT active.STOP
NOT OK - The diagnostic trouble code remains active. The sensor is not the cause of the diagnostic trouble code. Proceed to Test Step 2.Test Step 2. CHECK FOR A SHORT IN THE HARNESS.
The sensor remains disconnected from the machine harness.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the J1 and J2 machine harness connectors from the transmission ECU.
At the J1 machine harness connector for the ECU, measure the resistance between the signal contact J1-8 (wire E906-OR) to all other J1 and J2 contacts.Expected Result:Each resistance measurement is greater than 5000 ohms.Results:
OK - The resistance that is measured is greater than 5000 ohms for each measurement. The harness is correct. The ECU may have failed. Proceed to Test Step 3.
NOT OK - The resistance that is measured is NOT greater than 5000 ohms for each measurement. The machine harness has failed.Repair: There is a short in the machine harness. The short is between the signal circuit (wire E906-OR) and the circuit with the low resistance measurement. Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK IF THE DIAGNOSTIC TROUBLE CODE REMAINS
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 vehicle.
Check the status of the CID 0673