DIAPHRAGM 1125360 - Caterpillar

Conditions Which Generate This Code:The close breaker control output drives the Breaker Control Relay (BCR). The BCR activates the generator circuit breaker. The generator circuit breaker connects the generator to the bus. The inactive level of this output is floating. The voltage may range from 5.2 DCV to the voltage of the + battery terminal. The active voltage level is at the voltage of the battery negative terminal ("B-").For Automatic Synchronization, the output of the close breaker control is pulsed active for a programmed period of time. The period of time is set according to setpoint P302. While the conditions for synchronization are satisfied, the close breaker control output is repeatedly activated at one second intervals. When the breaker sensor input indicates that the generator circuit breaker is closed, the activation of the close breaker control output is discontinued. Also, the activation of the close breaker input is discontinued when setpoint P314 (Maximum Synchronization Time) is exceeded.For SemiAutomatic synchronization or Permissive synchronization, the close breaker control output is held active while the conditions for synchronization are met.A possible cause of a CID 0858 FMI 03 is a short to the battery positive terminal ("B+") of the signal for the close breaker control output. A CID 0858 FMI 03 is only detected when the GSC+P is attempting to activate the output of the "close breaker control". The GSC+P treats a CID 0858 FMI 03 as an alarm fault. CID 0858 FMI 03 will cause the GSC+P to stop the synchronization process until the FMI 03 is cleared and the diagnostic code is corrected.Test Step 1. CHECK THE INACTIVE VOLTAGE LEVEL OF THE CLOSE BREAKER CONTROL OUTPUT.
Turn the "ECS" switch to STOP.
Locate the wire that connects pin 37 on the GSC+P and terminal 11 on the Parallel Mode Switch.
Remove the wire from terminal 11 on the Parallel Mode Switch only. GSC+P remains connected to the wire.
Use a cable probe to measure the voltage at pin 37 on the GSC+P.Expected Result:The voltage should measure 5.2 1.0 DCV.Results:
OK - The voltage measures 5.2 1.0 DCV. The voltage is correct. Proceed to test step 2.
NOT OK - The voltage is less than 4.2 DCV or the voltage greater than 6.2 DCV. Repair: The GSC+ may have failed. It is unlikely that the GSC+ has failed. Exit this procedure and perform this entire procedure again. If the problem remains, replace the GSC+. See Testing And Adjusting, "EMCP Electronic Control (Generator Set) - Replace". Stop.Test Step 2. CHECK THE ACTIVE VOLTAGE LEVEL OF THE CLOSE BREAKER OUTPUT.
The wire from terminal 11 on the Parallel Mode Switch remains disconnected.
Start the engine and run the engine.
Perform the Permissive Paralleling function. If necessary, refer to Systems Operation, "Synchronization Sequence Of Operation".
Manually bring the engine into synchronization with the bus. The synchroscope pointer will be at the top center position. This position indicates a phase angle of zero degrees.Expected Result:When the "IN SYNC" symbol is turned ON, the voltage level of the close breaker control output should