SEAL-CLG SYS 3585828 - Caterpillar

Table 1
FNR Switch Position Input Circuit Signals    
Position     FNR Sensor 1 Duty Cycle (Percent) at ECM Contact J2-48 (wire A887-BU)     FNR Sensor 2 Duty Cycle (Percent) at ECM Contact J2-49 (wire A889-GY)    
Forward     85 5     85 5    
Neutral     50 10     50 10    
Reverse     13 7     13 7    The FNR Switch 1 sensor receives power and ground from the Machine ECM 10 volt power supply. The FNR Switch 2 sensor receives power and ground from the Machine ECM 8 volt power supply. The ECM will activate a diagnostic code when a problem is detected in one or both of the FNR Switch input circuits. When the ECM detects an abnormal condition in one switch circuit, the ECM will activate either a CID 2993 (FNR sensor 1) or a CID 2994 (FNR sensor 2 diagnostic code. When this condition occurs, the ECM will allow normal machine operation to continue. The ECM will use the one good PWM input signal in order to determine the state of the switch.If a diagnostic code is active for one of the switch input circuits and the Machine ECM detects a problem in the other input circuit, the ECM will interrupt normal operation and shift the drive to NEUTRAL. The ECM will not be able to determine the position status of the switch. The forced shift to NEUTRAL indicates that both of the switch input circuits are not operating correctly. When this occurs, the ECM will activate a CID 3527 diagnostic code.Note: If a diagnostic code is active for either the ECM 10 volt power supply (CID 1482) or the ECM 8 volt power supply (CID 0041), resolve the power supply problem before performing this procedure.This procedure should not require entry into any enclosures that contain hazardous voltage components and should not require any hazardous voltage connections to be disconnected.When an area that contains hazardous voltage components must be entered for a service procedure, the "Safe Shutdown Procedure for Electric Drive Tractors" procedure must be performed before any enclosures that contain hazardous voltage components are opened or before any hazardous voltage connectors are disconnected. Refer to the Troubleshooting, "Electrical Maintenance Guidelines" section of this manual. Perform the "Safe Shutdown Procedure for Electric Drive Tractors" procedure before any of the hazardous voltage areas are opened or before hazardous voltage connectors are disconnected.Note: The following test procedure may cause other diagnostic codes to be activated. Ignore these created diagnostic codes and clear the diagnostic codes when the problem has been corrected. Ensure that the CID 2993 FMI 08 diagnostic code is active before performing this procedure.Test Step 1. CHECK THE SWITCH OPERATION
Turn the disconnect switch and the key switch to the OFF position.
At the 12 contact harness connector for the FNR Switch, use a 151-6320 Removal Tool or a similar tool to remove the FNR 1 signal circuit at contact 7 (wire A887-BU) from the harness connector. The