WHEEL 3106095 - Caterpillar

Table 1
Coil Resistance for TOS Sensor    
Speed Sensor Part #     Sensor Coil Resistance    
3E-8848     1100 100 ohms @25° C (77° F)    
183-5011    
193-2550    
318-1178     1450 180 ohms @
25° C (77° F)    Expected Result:The resistance is within the range listed in Table 1. Results:
OK - The TOS sensor circuit resistance is within the listed range.The speed sensor and the internal harness for the transmission have not failed. Proceed to Test Step 3.
NOT OK - The TOS sensor circuit resistance is NOT within the listed range. The speed sensor and the internal harness for the transmission have failed. Proceed to Test Step 2.Test Step 2. CHECK THE RESISTANCE OF THE SENSOR
Disconnect the speed sensor from the internal harness of the transmission.
Measure the resistance between the two contacts of the connector for the speed sensor. Expected Result:The resistance is within the range listed in Table 1. Results:
OK - The TOS sensor resistance is within the listed range.Repair: The internal harness for the transmission has failed. Repair the internal harness for the transmission or replace the internal harness for the transmission. STOP
NOT OK - The TOS sensor resistance is NOT within the listed range. Repair: The speed sensor has failed. Replace the sensor. Adjust the speed sensor properly when the sensor is installed. See Testing and Adjusting, "Speed Sensor - Adjust". STOPTest Step 3. CHECK THE SIGNAL CIRCUIT FOR AN OPEN IN THE MACHINE HARNESS
The key start switch is OFF and the machine harness is disconnected from the internal harness of the transmission at the transmission case.
At the machine harness connector for the transmission, place a jumper between the two contacts that correspond to the sensor.
Disconnect the machine harness connector J2 from the ECM.
At the J2 harness connector, measure the resistance between the positive signal contact and the negative signal contact for the suspect sensor. Expected Result:There should be less than 5.0 ohms resistance. Results:
OK - There is less than 5.0 ohms resistance. The machine harness is correct. Proceed to Test Step 4.
NOT OK - There is not less than 5.0 ohms resistance. Repair: There is an open circuit in the machine harness. The open is in positive signal wire or the negative signal wire of the machine harness. Repair the machine harness or replace the machine harness. STOPTest Step 4. CHECK THE SIGNAL CIRCUIT FOR A SHORT
If a jumper was used in a previous step, remove the jumper.
Reconnect the machine harness to the internal harness of the transmission at the transmission case.
At the J1 and J2 harness connectors, measure the resistance between the + signal contact (J2-25) and all sources of positive voltage and ground. The possible sources of positive voltage are contacts J1-1, J1-4, J1-6, J1-8, J1-10, J1-11, J1-12, J1-17, J1-18, J1-40, J2-1, J2-2, J2-7, J2-8, J2-13, J2-19, and J2-37. The possible sources of ground are contact J1-2, contact J1-5, contact J1-7, contact J1-15, contact J1-16, contact J2-3 and frame ground.
At the J1 and J2 harness connectors, measure the