- Connect Cat ET to the machine.
- Turn the keyswitch on.
- Start Cat ET.
Cat ET will initiate communication 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, see the test procedure for the desired diagnostic code.
ReferenceTroubleshooting, "Service Tools"
Active Diagnostic Codes
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| Illustration 1 | g02355999 |
Typical Cat® Electronic Technician (Cat ET) Service Tool screen for active diagnostic codes | |
Cat ET has an active diagnostic code screen. The screen shows component identifier (CID), failure mode identifier (FMI), and text description of the problem.
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. Perform the desired procedure, then clear any diagnostic codes caused by that procedure.
Note: Before performing a procedure, always check all the circuit breakers. Repair the cause of any circuit breaker that is tripped.
Logged Diagnostic Codes
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| Illustration 2 | g02356001 |
Typical Cat ET screen for logged diagnostic codes | |
Cat ET has a logged diagnostic code screen. On the logged diagnostic code screen, Cat ET will log diagnostic codes that are intermittent. The logged diagnostic data includes component identifier (CID), failure mode identifier (FMI), and text description of the problem. Also, the logged diagnostic data includes the number of occurrences of the problem and two time stamps. The time stamps display the first occurrence and 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 1000 hours of machine operation.