C27 and C32 Tier 4 Engines Caterpillar

Use this procedure in order to troubleshoot a high differential pressure for the air inlet system. Also, use this procedure if one of the following event codes are active. Access the engine monitoring system on Caterpillar Electronic Technician (ET) in order to view the current trip points for these codes. Refer to Troubleshooting, "Engine Monitoring Parameters" for information about engine events.

Table 1

Engine Events
J1939 Code and Description	Conditions that Generate the Code	System Response
107-15 Engine Air Filter 1 Differential Pressure : High - least severe (1)	The air filter differential pressure is above the trip point pressure for the delay time.	The code is logged.
107-16 Engine Air Filter 1 Differential Pressure : High - moderate severity (2)

Probable Causes

• Air filter element

• Air inlet piping

• Atmospheric pressure sensor, turbocharger compressor inlet pressure sensors, and/or sensor circuits

• Enclosure

Recommended Actions

Air Filter Element

Check the air intake system for plugged air filters or for damaged air filters. If the engine is equipped with an air intake precleaner, verify the proper operation of the air intake precleaner.

Air Inlet Piping

Check the air inlet piping for damage or restrictions. Repair the piping or replace the piping.

Enclosure

Check that the engine has been installed in an enclosure that is sufficiently ventilated. Repair the ventilation for the enclosure.

Atmospheric Pressure Sensor, Turbocharger Compressor Inlet Pressure Sensors, and/or Sensor Circuits

Use Cat ET to compare the status of the following parameters while the engine is off:

• "Atmospheric Pressure"

• "Turbocharger #1 Compressor Inlet Pressure"

• "Turbocharger #2 Compressor Inlet Pressure"

Note: The status for air filter restriction is a calculated value. Before Cat ET reports the status parameters for air filter restriction, the engine must be running for three minutes. Cat ET will report "Conditions Not Met" for these parameters prior to this delay time.

Cat ET will report the status for "Atmospheric Pressure" as the barometric pressure that is for the surrounding area. While the engine is off, the readings for the turbocharger compressor inlet pressure sensor will be approximately the same value as the atmospheric pressure sensor. If the readings do not agree, troubleshoot the sensor circuit for the suspect sensor. Refer to Troubleshooting, "Sensor Signal (Analog, Active) - Test" for information that is related to troubleshooting the circuits.