WHEEL GP-FDR&- 2389909 - Caterpillar

The ECM detects a communication failure with the TCO signal (torque converter output) and the two TOS signal (transmission output speed). The communication failure may be due to an incorrect or corrupted ECM configuration. The communication failure may also be due to disconnected connectors for the sensors or a faulty wiring harness for the sensors. The failure can also be due to mechanical resonance that can disrupt the TCO signal.System Response:The ECM will log the diagnostic code. The diagnostic code may be viewed on the Caterpillar Electronic Technician (Cat® ET). The machine shifting will be inhibited.Test Step 1. CHECK THE TRANSMISSION CHASSIS ECM FOR PROPER CONFIGURATION AND SOFTWARE
Use Cat® ET to determined that the transmission serial number, entered in the ECM, is correct.
Verify that the ECM Transmission Configuration parameters are correct
Verify that the version of software used, is compatible. Note: Consult your Cat dealer for the correct part numbers of the flash software.Expected Result:The transmission serial number and configuration is correctly entered. The proper version of software is installed.Results:
OK - ECM configuration is correct and the version of software is compatible. Proceed to test step 3.
NOT OK - ECM configuration is not correct or the proper software is not installed. Repair: Correct the ECM configuration or if needed, flash the proper software to the ECM. Refer to Testing and Adjusting, "Electronic Control Module (ECM) - Flash Program" section in this manual. Cycle the keyswitch in order to initialize new software. Ensure that the diagnostic code is no longer active.STOPTest Step 2. CHECK THE RETURN CIRCUITS
Table 1
Sensor Circuits
Sensor ECM Contact Component Contact Circuit
Transmission Input Speed Sensor J2-30 1 E909-WH(White)
J2-36 2 E908-BR(Brown)
TOS Speed Sensor 1 J2-14 1 E901-GN(Green)
J2-20 2 E900-WH(White)
TOS Speed Sensor 2 J2-31 1 E907-GY(Grey)
J2-25 2 E906-OR(Orange) Note: Refer to table 1 when performing the following tests steps.
Place the disconnect switch and the key start switch in the OFF position.
Disconnect the machine harness from the sensors.
At the machine harness connector for the sensors, measure the resistance between contact 1 and frame ground for each sensor. Expected Result:The resistance should measure 5 ohms or less for each sensor.Results:
OK - The return circuit is correct. Proceed to test step 3.
NOT OK - The return circuit in the machine harness has excessive resistance (open) for one or more of the measurements.Repair: Repair or replace the machine harness.STOPTest Step 3. CHECK THE SIGNAL CIRCUIT FOR AN OPEN IN THE MACHINE HARNESS
Place a jumper between the two contacts of the machine harness connector for the speed sensors.
Disconnect connectors J1 and J2 from the machine harness of the ECM.
Measure the resistance from the sensor signal wire to the return contact wire of the machine harness for each sensor. Expected Result:There should be continuity (less than 5.0 ohms resistance). Results:
OK - The signal circuit in the machine harness is correct. Proceed to test step 4.
NOT OK - There is an open in the signal circuit of the machine harness for one or more of the sensors.Repair: Repair or replace the machine harness.STOPTest Step 4. CHECK THE