ENGINE AR-PRIMARY 3895644 - Caterpillar

The Electronic Control Module (ECM) detects inlet air restriction that is above the default pressure. Information on default settings and ranges for this event can be found in Troubleshooting, "Event Codes".System Response:The event is logged. When the air inlet restriction exceeds 7 kPa (28 inches of H2O) the ECM will derate the engine. The ECM will derate the engine in increments of 2 percent per 1 kPa (4 inches of H2O) up to a maximum derate level of 25 percent. Air filter restriction is determined by measuring the atmospheric pressure and the turbocharger inlet pressures and calculating the difference.Possible Performance Effect:Low powerTroubleshooting:
There may be a problem with the air inlet system.
There may be a problem with the atmospheric pressure sensor or the left or right turbocharger inlet pressure sensors.Test Step 1. Check for "ACTIVE" Diagnostic Codes.
Start the Caterpillar Electronic Technician (ET).
Turn the main power to the ON position.
Check for any active diagnostic codes or logged diagnostic codes. Expected Result:No diagnostic codes are present.Results:
OK - No diagnostic codes are present. Proceed to Test Step 2.
Not OK - Diagnostic codes are present.Repair: Repair the diagnostic codes that are present. Refer to the appropriate topic in the "Troubleshooting With a Diagnostic Code" section of this manual. Ensure that the repair eliminates the problem.STOPTest Step 2. Perform a Check of the Air Inlet System.
Check for restrictions in the air inlet system. Check the air filter. Expected Result:There are no problems with the air inlet system.Results:
OK - There are no problems with the air inlet system. There may be an intermittent problem.Repair: Monitor the operation of the engine. Repair the problem. Ensure that the repair eliminates the problem.STOP
Not OK - There is a problem with the air inlet system.Repair: Repair the problem. Ensure that the repair eliminates the problem.STOP