COUNTERWEIGHT 9C5621 - Caterpillar

Illustration 1 g02969736
Schematic of the temperature sensor (rear axle oil)This diagnostic code is associated with the rear axle oil temperature sensor. The FMI 04 means that the Machine Electronic Control Module (ECM) has determined that the voltage of the sensor signal circuit is below normal.The sensor resistance range is 33,650 ohms at −40° C (−40° F) to 18.6 ohms at 150° C (302° F). The following table indicates the approximate sensor resistance between contacts 1 and 2 at different sample temperatures.
Table 1
Front Axle Oil Temperature Sensor Resistance at Indicated Temperatures    
Oil Temperature     Resistance (Ohms)    
0° C (32° F)     3268    
20° C (68° F)     1250    
40° C (104° F)     532    
70° C (158° F)     175    
80° C (176° F)     126    
90° C (194° F)     92    
100° C (212° F)     68    
115° C (239° F)     45    
125° C (257° F)     34    
130° C (266° F)     30    The possible causes of this diagnostic code are listed below:
The signal circuit for the sensor is shorted to ground
The sensor has failed
The ECM has failed. The ECM is unlikely to have failedNote: Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean, that all connections are secure and that all connections are in good condition. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure. 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 CID 0428 FMI 04 is active before performing 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 code is active.
While observing the status of the diagnostic code, disconnect the sensor from the machine harness.Expected Result:CID 0428 FMI 04 changes to a CID 0428 FMI 03 diagnostic code when the sensor is disconnected from the machine harness.Results:
YES - CID 0428 FMI 04 changes to a CID 0428 FMI 03 diagnostic code when the sensor is disconnected. The sensor has failed.Repair: The sensor is causing the problem. Replace the temperature sensor.STOP
NO - Disconnecting the sensor from the machine harness did not change the status for the active diagnostic code. The CID 0428 FMI 04 diagnostic code is still active. The sensor is not causing the problem. Proceed to Test Step 2.Test Step 2. CHECK THE SENSOR CIRCUIT FOR A SHORT
The sensor remains disconnected from the machine harness.
Turn the disconnect switch and the key switch to the OFF position.
Disconnect the machine harness connector J1 and J2 from the Machine ECM.
At the machine harness connector for the ECM, measure the resistance from the signal contact