RING-PISTON 1P1124 - Caterpillar

Conditions Which Generate This Code:This diagnostic code is associated with an electrical system voltage that is above normal. The FMI 03 means that the engine electronic control module (ECM) has determined that the electrical system voltage is above normal.
Illustration 1 g00794517
System Schematic For Battery Voltages The EMCP II+ monitors the battery voltage in order to protect the EMCP II+ from a battery problem or from a charging problem. The battery voltage is received from the engine electronic control module (ECM) by the CAT data link. If you receive a CID 168 E diagnostic code, refer to Troubleshooting, RENR2227, "3406E and 3456 Generator Set Engines". The GSC+ generates a CID 168 FMI 03 as an alarm fault. The threshold for a CID 168 FMI 03 for battery voltage is greater than 32 DCV for 24 volt system. The threshold for a CID 168 FMI 03 for battery voltage is greater than 45 DCV for a 32 volt system.
Table 1
POSSIBLE CAUSES FOR CID 168 DIAGNOSTIC CODES    
Location of the Display for the Diagnostic Code     Diagnostic Code     Battery Voltage (Threshold)
24 Volt (System Voltage)     Battery Voltage (Threshold)
32 Volt (System Voltage)    
Engine ECM     CID168 E00     The engine is running and the battery voltage is greater than 32 DCV more than two seconds.        
Engine ECM     CID 168 E01     The engine is not running and the battery voltage is less than 9 DCV for more than two seconds.        
Engine ECM     CID 168 E02     The engine is not running.
The battery voltage is less than 9 DCV for a period of .07 seconds. The battery voltage then returns to 9 DCV or the battery voltage rises above 9 DCV.
A second cause for this diagnostic code is possible. The battery voltage will drop below 9 DCV three times in seven seconds.        
GSC+     CID 168 E03         Regardless of engine status, the battery voltage is greater than the P007 limit.    
GSC+     CID 168 E04         Regardless of the engine status, the battery voltage is less than 18 DCV.    The setpoint for the system voltage (P007) specifies the battery voltage.24 - 24 Volt System32 - 32 Volt SystemNote: The GSC+ does not receive battery power when the engine control switch (ECS) is in the OFF/RESET position. When contact 6 is connected to one of the contacts (8, 9, 10), the GSC+ receives battery power when the ECS is in the OFF/RESET position. Before beginning this procedure, ensure that the following steps have been performed:
VERIFY THE DIAGNOSTIC CODE.
Make sure that the CID 168 FMI 03 is shown on the display.
Enter service mode.
Turn the ECS to the STOP position.Note: When the Program Setpoint P023 is set to 0, the GSC+ is programmed for a MUI engine. The engine's electronic control module (ECM) is eliminated as a possibility of the problem.Test Step 1. CHECK THE SYSTEM'S VOLTAGE.
Turn the ECS to the STOP.
Measure the voltage across the