ROD 1306883 - Caterpillar

Table 1
Associated Codes
J1939 Code CDL Code
108-3 3528-3
108-4 3528-4 Note: Cat ET will report the status for atmospheric pressure as the ambient barometric pressure. The readings for the turbocharger inlet pressure sensor will be approximately the same value that is reported by the atmospheric pressure sensor. The approximate same value readings will occur while the engine is not running. If the readings do not agree, troubleshoot the sensor circuit for the suspect sensor.Reference: Refer to Troubleshooting, "Sensor Signal (Analog, Active) - Test".Probable Causes
Associated codes
Boost Leak
Engine operating conditions
Failed exhaust balance valve
High altitude
Obstructed aftercooler
Table 2
Troubleshooting Test Steps Values Results
1. Check for Associated Codes
A. Establish communication between Cat® Electronic Technician (ET) and the ECM . Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Determine if a code is active or logged.
Associated Codes
Result: An associated diagnostic code is not active or logged.
Proceed to Test Step 2.
Result: An associated code is active or logged.
Repair: Troubleshoot the associated code. Refer to Troubleshooting, "Diagnostic Trouble Codes" to troubleshoot the associated diagnostic code.
Table 3
DTC with associated derate? Data logged in this histogram? Interpretation
No Yes Derate was probably caused by the exhaust temperature derate.
Yes Yes There may be multiple causes for derate since this exhaust temperature histogram only logs data when it has the largest derate ( another derate may have been active due to a diagnostic trouble code, but a larger exhaust temperature derate was applied).
Yes No Derate was probably not caused by the exhaust temperature derate.
Illustration 1 g02893159
Example of Cat ET screenshot of the histogram. This histogram is populated when the engine system has calculated a condition in which high exhaust temperatures are present. A fault code will not be logged when the system calculates a high exhaust temperature condition, but will activate a de-rate to the engine to protect the engine system. This is normal under most circumstances and no additional troubleshooting is necessary.
Note: Information from this histogram is to be used with active and logged codes. This histogram is informational if no codes are active or logged.
Table 4
Troubleshooting Test Steps Values Results
2. Check for Boost Leakage
A. Apply a light load to the engine and check for boost leakage.
Boost Leaks
Result: Boost leakage was not found.
Proceed to Test Step 3.
Result: Boost leakage was found.
Repair: Repair the leaks. Return the unit to service.
3. Check the Engine Operating Conditions
A. Check the histogram to determine if the high exhaust temperature was due to normal operation.
B. When possible, interview the operator. Determine if the engine is being operated under heavy load. Ensure that the engine is being operated at the proper engine speed.
C. If derates are suspected, reset histogram and return the unit to service. If the histogram repopulates without fault codes, the derate was under normal engine operation.
Normal Operation
Result: The code was not logged during a heavy load.
Proceed to Test Step 4.
Result: The code was logged during a heavy load.
Repair: Reduce the load on the engine. Return the unit to service.
4. Check the Exhaust Balance Valve
A. An exhaust balance valve that has failed in the closed position can cause high