Perform the following steps to use the Cat® Electronic Technician (Cat) ET service tool to determine diagnostic codes:
- Connect Cat ET to the machine.
- Turn the keyswitch to the RUN position.
- Start Cat ET.
Cat ET will initiate communications with the electronic control modules (ECMs) on the machine. After communication has been established, Cat ET will list the ECMs.
- Select the desired ECM.
- After the diagnostic codes have been determined with Cat ET, refer to the test procedure for the corresponding diagnostic code.
ReferenceTroubleshooting, "Service Tools"
Active Diagnostic Codes
Typical Cat® ET screen for active diagnostic codes
The following procedures may cause new diagnostic codes to be logged. Therefore, before any procedures are performed, make a list of all the active diagnostic codes in order to determine the system problems. Clear the diagnostic codes that were caused by the procedure, when each procedure is complete.
Note: Before performing a procedure, always check all the circuit breakers. Repair the cause of any circuit breaker that is tripped.
A screen is provided in Cat ET for active diagnostic codes. The screen will display the diagnostic codes that are active. Active diagnostic information shall include a component identifier (CID), a failure mode identifier (FMI) and a text description of the problem.
Logged Diagnostic Codes
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. Cat ET will log diagnostic codes that are intermittent. The logged diagnostic data shall include a component identifier (CID), a failure mode identifier (FMI), and a text description of the problem. Also, the logged diagnostic data shall include the number of occurrences of the problem and two time stamps. The time stamp displays the first occurrence of the problem and the time stamp displays the most recent occurrence of the problem.
Diagnostics are logged in non-volatile memory. On powerup, the ECM will clear any diagnostic codes that have not been detected or active within the last 150 hours of machine operation.