Using Cat® Electronic Technician (Cat ET) Service Tool to Determine Diagnostic Codes
Perform the following steps to use Cat® Electronic Technician (Cat ET) Service Tool to determine diagnostic codes:
- 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.
Reference: Troubleshooting, "Service Tools"
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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 "Active Diagnostic Code" 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. Clear any diagnostic codes caused by the procedure.
Note: Before performing a procedure, always check all the circuit breakers. Repair the cause of any circuit breaker that is tripped.
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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 a 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.
Using the Graphic Display to Determine Diagnostic Codes
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Illustration 3 | g06014696 |
(1) Service button
(2) BACK button (3) OK button (4) UP Arrow button (5) DOWN Arrow button |
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Illustration 4 | g06014717 |
- Press the Service button (1) on the right side of the Display. The Service menu page will appear.
- Press the "Diagnostics" button. The "Diagnostics" button will highlight in yellow and the Diagnostics page will appear.
Show/hide table
Illustration 5 g06014683 - Navigate the Diagnostic "Events" list by pressing the UP (4) and DOWN (5) arrow buttons.
- Press an Event. The Event will highlight in yellow and the Detail page will appear with more information.
- Press the BACK button (2) to return to the previous menu.