8S7794 CORE ASSEM. Caterpillar parts
12F, 14E
Rating:
Alternative (cross code) number:
CA8S7794
8S-7794
8S7794
CA8S7794
8S-7794
8S7794
Weight: 98 pounds 44 kg.
MOTOR GRADER,
Information:
This diagnostic code is recorded when the diagnostic circuit in the Product Link identifies a system voltage that is above 32 VDC.The possible causes of this fault are listed below:
A charging system component is faulty.
The harness wiring is faulty.
The Product Link is faulty, however a faulty Product Link is unlikely.Note: Determine if a battery charger or a welder is being used on the machine. Disconnect the charger or the welder if one is used. Recheck for the diagnostic code.Test Step 1. CHECK THE SYSTEM VOLTAGE AT THE PRODUCT LINK.
Start the engine and operate the engine at a high idle for 5 to 10 minutes.
Measure the system voltage between the "Unswitched Power" and the "Ground" contacts. Pin 52 is the terminal for "Unswitched Power" and pin 65 is the terminal for "Ground". Expected Result:The voltage is 11 VDC to 32 VDC.Results:
OK - The voltage is 11 VDC to 32 VDC. The Product Link should not be logging this diagnostic code.Repair: Use the Caterpillar Electronic Technician (Cat ET) in order to clear the diagnostic code from the Product Link. If the voltage is correct and the Product Link records the diagnostic code again, the Product Link may need to be replaced. Before replacing the Product Link, contact your Caterpillar Technical Communicator.STOP
NOT OK - The voltage is not 11 VDC to 32 VDC. Proceed to Test Step 2.Test Step 2. CHECK THE ALTERNATOR.
Run the engine at high idle for 5 to 10 minutes.
Measure the voltage output at the battery posts. Expected Result:The voltage should be below 32 VDC.Results:
OK - The voltage is below 32 VDC. The battery could be faulty. Proceed to Test Step 3.
NOT OK - The voltage is above 32 VDC. Troubleshoot the alternator. The voltage regulator could be faulty. If conditions are not resolved, proceed to Test Step 3.Test Step 3. CHECK THE BATTERY VOLTAGE.Turn the key start switch to the OFF position. Measure the battery voltage at the battery posts.Expected Result:The voltage should be below 32 VDC.Results:
OK - The voltage is below 32 DCV. Proceed to Test Step 4.
NOT OK - The voltage is above 32 VDC.Repair: Refer to Special Instruction, REHS0354, "Charging System Troubleshooting".If conditions are not resolved, proceed to Test Step 4.Test Step 4. CHECK EVERY ECM ON THE MACHINE.Check the logged diagnostics of any other ECM that is installed on the machine. Compare each ECM that has logged the "CID 168 FMI 00" code in the same time period.Note: The Service Meter Hours (SMH) on the logs may be different. The difference between the current SMH and the logged SMH is important.Expected Result:Other "CID 168 FMI 00" diagnostic codes can be found on other Electronic Control Modules (ECM).Results:
YES - "CID 168 FMI 00" diagnostic codes are found on other Electronic Control Modules (ECM).Repair: Clear the fault if all the following conditions occur:
A problem is not found with the charging system.
A problem is not found with the wiring.
The fault has occurred a few times.Monitor the module and the machine for further occurrences. If the fault
A charging system component is faulty.
The harness wiring is faulty.
The Product Link is faulty, however a faulty Product Link is unlikely.Note: Determine if a battery charger or a welder is being used on the machine. Disconnect the charger or the welder if one is used. Recheck for the diagnostic code.Test Step 1. CHECK THE SYSTEM VOLTAGE AT THE PRODUCT LINK.
Start the engine and operate the engine at a high idle for 5 to 10 minutes.
Measure the system voltage between the "Unswitched Power" and the "Ground" contacts. Pin 52 is the terminal for "Unswitched Power" and pin 65 is the terminal for "Ground". Expected Result:The voltage is 11 VDC to 32 VDC.Results:
OK - The voltage is 11 VDC to 32 VDC. The Product Link should not be logging this diagnostic code.Repair: Use the Caterpillar Electronic Technician (Cat ET) in order to clear the diagnostic code from the Product Link. If the voltage is correct and the Product Link records the diagnostic code again, the Product Link may need to be replaced. Before replacing the Product Link, contact your Caterpillar Technical Communicator.STOP
NOT OK - The voltage is not 11 VDC to 32 VDC. Proceed to Test Step 2.Test Step 2. CHECK THE ALTERNATOR.
Run the engine at high idle for 5 to 10 minutes.
Measure the voltage output at the battery posts. Expected Result:The voltage should be below 32 VDC.Results:
OK - The voltage is below 32 VDC. The battery could be faulty. Proceed to Test Step 3.
NOT OK - The voltage is above 32 VDC. Troubleshoot the alternator. The voltage regulator could be faulty. If conditions are not resolved, proceed to Test Step 3.Test Step 3. CHECK THE BATTERY VOLTAGE.Turn the key start switch to the OFF position. Measure the battery voltage at the battery posts.Expected Result:The voltage should be below 32 VDC.Results:
OK - The voltage is below 32 DCV. Proceed to Test Step 4.
NOT OK - The voltage is above 32 VDC.Repair: Refer to Special Instruction, REHS0354, "Charging System Troubleshooting".If conditions are not resolved, proceed to Test Step 4.Test Step 4. CHECK EVERY ECM ON THE MACHINE.Check the logged diagnostics of any other ECM that is installed on the machine. Compare each ECM that has logged the "CID 168 FMI 00" code in the same time period.Note: The Service Meter Hours (SMH) on the logs may be different. The difference between the current SMH and the logged SMH is important.Expected Result:Other "CID 168 FMI 00" diagnostic codes can be found on other Electronic Control Modules (ECM).Results:
YES - "CID 168 FMI 00" diagnostic codes are found on other Electronic Control Modules (ECM).Repair: Clear the fault if all the following conditions occur:
A problem is not found with the charging system.
A problem is not found with the wiring.
The fault has occurred a few times.Monitor the module and the machine for further occurrences. If the fault
Caterpillar parts catalog:
Parts core Caterpillar catalog:
2D2628
CORE-VALVE
120, 120G, 12E, 12F, 140, 14E, 2470C, 2570C, 2670C, 2864C, 414E, 416, 416B, 416C, 416D, 416E, 416F, 420D, 420E, 420F, 422E, 424D, 426, 426B, 426C, 428, 428B, 428D, 428E, 430D, 430E, 430F, 432D, 432E, ...
120, 120G, 12E, 12F, 140, 14E, 2470C, 2570C, 2670C, 2864C, 414E, 416, 416B, 416C, 416D, 416E, 416F, 420D, 420E, 420F, 422E, 424D, 426, 426B, 426C, 428, 428B, 428D, 428E, 430D, 430E, 430F, 432D, 432E, ...
5J5148
CORE
120H, 120H ES, 120H NA, 12G, 12H ES, 12H NA, 130G, 135H, 140G, 140H ES, 140H NA, 14E, 14G, 16, 160H ES, 160H NA, 16G, 225, 227, 229, 615, 621B, 621E, 623, 627B, 631C, 631E, 633D, 637D, 637E, 639D, 651...
120H, 120H ES, 120H NA, 12G, 12H ES, 12H NA, 130G, 135H, 140G, 140H ES, 140H NA, 14E, 14G, 16, 160H ES, 160H NA, 16G, 225, 227, 229, 615, 621B, 621E, 623, 627B, 631C, 631E, 633D, 637D, 637E, 639D, 651...
7S1086
CORE ASSEM.
120, 12F, 920
120, 12F, 920
7S1085
CORE ASSEM.
140, 140B, 14E, 920, 930, 930R
140, 140B, 14E, 920, 930, 930R
9S4997
CORE AS
12F, 930
12F, 930
6D1257
CORE
12E, 14E
12E, 14E
2D2638
CORE
12F
12F
6D1257
CORE
12E, 14E
12E, 14E
2Y3535
CORE
140B
140B
4384587
CORE AS-RADIATOR
MH3037
MH3037
3942603
CORE AS-FUEL COOLER
12M 3, 12M 3 AWD, 140M 3, 140M 3 AWD, 160M 3, 160M 3 AWD
12M 3, 12M 3 AWD, 140M 3, 140M 3 AWD, 160M 3, 160M 3 AWD
1P6040
CORE
16
16
2D2638
CORE
12F
12F
5D0879
CORE
16
16