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| Illustration 1 | g00721914 |
System schematic for the programmable spare relays ("PSR1" and "PSR2") | |
The GSC+P uses the Programmable Spare Relay (PSR) in order to activate the customers' equipment. Refer to Systems Operation, "Spare Input/Output Programming OP6".
Note: Whenever the GSC+P activates or the GSC+P attempts to activate the PSR, K8 is shown on the lower display. When the PSR is not activated, K8 is not shown.
The possible cause of a CID 0448 FMI 12 is an open coil or a shorted coil of the PSR.
The system responses to these diagnostic codes are listed below.
- If a CID 0448 FMI 12 occurs and the PSR is active, any customer's equipment that is wired to RM-25 will be deactivated and any customer's equipment that is wired to RM-26 will remain activated.
- If a CID 0448 FMI 12 occurs and the PSR is inactive, any customer's equipment that is wired to RM-25 will remain deactivated and any customer's equipment that is wired to RM-26 will remain activated.
The GSC+P treats a CID 0448 FMI 12 as an alarm fault. Active alarm faults are shown on the display when the "Alarm Codes" key is pressed and the Engine Control Switch (ECS) is in any position except the OFF/RESET position. Clear the diagnostic code from the fault log after troubleshooting is complete.
This troubleshooting procedure is for an active CID 0448 or the troubleshooting procedure is for an inactive CID 448 FMI 12.
Test Step 1. CHECK THE STATUS OF THE DIAGNOSTIC CODE.
- Turn the ECS to the OFF/RESET position and then turn the ECS to the STOP position.
- Press the "Alarm Codes" key.
- Observe the upper display. Check that the CID 0448 FMI 12 is active.
- If the diagnostic code is not active, enter the Service Mode. View the fault log for a OP1. Check that the diagnostic code is inactive.
Expected Result:
A CID 0448 FMI 12 is displayed as an active diagnostic code or CID 0448 FMI 12 is displayed as an inactive diagnostic code.
Results:
- OK - The CID 0448 FMI 12 is active or the CID 0448 FMI 12 is inactive. Proceed to Test Step 2.
- NOT OK - The CID 0448 FMI 12 has not occurred. The diagnostic code is not active and the diagnostic code is not inactive.STOP
Test Step 2. CHECK THE INTERNAL CABLE OF THE RELAY MODULE.
Note: Only open the relay module in a dry environment. If the inspection and repair takes more than approximately twenty minutes replace the desiccant bag in the GSC+P housing. Refer to Testing And Adjusting, "Relay Module - Replace".
- Turn the ECS to the OFF/RESET position.
- Disconnect the negative battery cable.
- Temporarily, remove the relay module from the GSC+P. Refer to Testing And Adjusting, "Relay Module - Replace".
- Check the cable that attaches the relay module to the GSC+P.
Expected Result:
The cable should be firmly seated in the connector. The clamp should be in place. The cable should not be damaged.
Results:
- OK - The cable is firmly seated in the connector. The clamp is in place. The cable is not damaged. Reassemble the relay module to the GSC+P. Proceed to Test Step 3.
- NOT OK - One or more of the components are damaged or the components are missing.
Repair: Replace the clamp if the clamp is missing. If the cable is damaged, replace the GSC+P. Refer to Testing and Adjusting, "EMCP Electronic Control (Generator Set) - Replace".
STOP
Test Step 3. FUNCTIONAL CHECK OF THE PSR
- Turn the ECS to the OFF/RESET position.
- Reconnect the negative battery cable.
- Disconnect all wires from RM-25 of the relay module.
- Remove fuse "F9" from the relay module.
- At the relay module, measure the resistance from RM-25 to RM-11. Make a note of the resistance measurement.
- Turn the ECS to the START position. Measure the resistance from RM-25 to RM-11. Make a note of the resistance measurement.
Expected Result:
The initial resistance measurement after removing the wires and the fuse from the relay module should be greater than 5000 ohms. The resistance measurement should be less than 5 ohms when the ECS is placed in the START position.
Results:
- OK - The resistance measurements are correct. The problem does not exist at this time. The initial problem was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal operation and watch for a recurrence.STOP
- NOT OK - Either one of the resistance measurements are NOT correct. The relay module has failed.
Repair: Replace the relay module. Refer to Testing And Adjusting, "Relay Module - Replace".
STOP