CAP 4T1703 - Caterpillar

Probable Causes
Air inlet or exhaust system
Atmospheric pressure sensor
Flash file
Fuel quality
Valve adjustmentRecommended Actions
Table 1
Troubleshooting Test Steps Values Results
1. Check the Air Inlet System for Restrictions and/or for Leaks
A. Check for an air filter restriction.
B. Perform a visual inspection of the system for restrictions and/or for leaks in the air inlet piping .
C. Ensure that the turbocharger is in good repair.
Air Inlet System
Result: The air inlet system is NOT OK.
Repair: Repair or replace any worn or damaged components.
Result: The air inlet system is OK.
Proceed to Test Step 2.
2. Check the Atmospheric Pressure Sensor
A. Check the Caterpillar Electronic Technician (ET) for active diagnostic codes on the sensor. If no active diagnostic code exists, the sensor may be used.
50 kPa (7.25 psi) and 100 kPa (14.5 psi)
Result: The atmospheric pressure sensor is NOT OK.
Repair: Replace the atmospheric pressure sensor.
Result: The atmospheric pressure sensor is OK.
Proceed to Test Step 3.
3. Check the Flash File
A. Verify that the latest flash file is installed. Refer to Troubleshooting, "ECM Software - Install" for information.
Flash File
Result: The correct flash file is not found.
Repair: Download and install the correct flash file.
Result: The correct flash file is found.
Proceed to Test Step 4.
4. Check the Fuel Quality
A. Cold weather adversely affects the characteristics of the fuel. Refer to Operation and Maintenance Manual for information on improving the characteristics of the fuel during cold-weather operation.
Fuel Quality
Result: The fuel quality is poor.
Repair: Replace the fuel in the fuel tank.
Result: The fuel quality is OK.
Proceed to Test Step 5.
5. Check the Valve Adjustment
A. Refer to Systems Operation/Testing and Adjusting for information that is related to valve adjustments.
Valve Adjustment
Result: The valve adjustment is NOT OK.
Repair: Adjust the valves. Refer to Testing and Adjusting for more information on adjusting the valves.
STOP