Follow these steps to determine codes using CatTM Electronic Technician (Cat ET):
- Connect Cat ET to the machine.
- Turn the key start switch to RUN.
- Start Cat ET.
Cat ET will initiate communications with each Electronic Control Module (ECM) on the machine. After communication has been established, Cat ET will list each ECM.
- Choose the desired ECM.
- After the diagnostic codes have been determined with Cat ET, refer to the procedure for the corresponding diagnostic code.
Reference: Troubleshooting, "Service Tools"
Active Diagnostic Codes
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Illustration 1 | g00859671 |
Typical Cat ET screen for active diagnostic codes |
The following procedures may cause new diagnostic codes to be logged. Before any procedures are performed, make a list of all of the active diagnostic codes. Clear the diagnostic codes that were caused by the procedure after each procedure is complete.
Note: Before performing a procedure, check all of the circuit breakers. Repair any condition that has caused a circuit breaker to trip.
A screen is provided in Cat ET for active diagnostic codes. The screen will display the diagnostic codes that are active. Active diagnostic information includes a Component Identifier (CID), a Failure Mode Identifier (FMI), and a text description of the problem.
Logged Diagnostic Codes
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Illustration 2 | g00859762 |
Typical Cat ET screen for logged diagnostic codes |
A screen is provided in Cat ET for logged diagnostic codes. The screen will display diagnostic codes that are logged. The Cat ET will log diagnostic codes that are intermittent. The diagnostic data that is logged includes a CID, an FMI, and a text description of the problem. Also, the diagnostic data that is logged shall include the number of occurrences of the problem and two time stamps. The time stamp displays the first occurrence of the problem. The time stamp also displays the most recent occurrence of the problem.
Diagnostics are logged in non-volatile memory. On power up, the ECM will clear any diagnostic codes that have not been detected or active within the last 150 hours of machine operation.