COUPLER AS 4855225 - Caterpillar

Table 1
Diagnostic Trouble Codes for High Intake Manifold Air Pressure
J1939 Code Description Notes
1127-16 Engine Turbocharger 1 Boost Pressure : High - moderate severity (2) The Electronic Control Module (ECM) detects that the actual intake manifold air pressure is greater than the desired intake manifold air pressure by 50 kPa (7.25 psi) for at least 10 seconds.
If equipped, the warning lamp will flash. The engine will be derated.
If the actual intake manifold pressure is within 25 kPa (3.6 psi) of the desired intake manifold air pressure for at least 11 minutes, the code will reset. Probable Causes
Air inlet and exhaust restrictions
Turbocharger wastegate
Wastegate regulatorRecommended Actions
Note: The procedures have been listed in order of probability. Complete the procedures in order.
Table 2
Troubleshooting Test Steps Values Results
1. Air Inlet and Exhaust Restrictions
A. Check the air filter for damage.
B. Check the air inlet and exhaust system for restrictions and/or leaks. Refer to Systems Operation, Testing, and Adjusting, "Air Inlet and Exhaust System - Inspect".
Air inlet and exhaust system
Result: Defects found in the air inlet or exhaust systems.
Repair: Repair any defects. Replace damaged components.
Result: The air inlet and exhaust systems are OK.
Proceed to Test Step 2.
2. Turbocharger Wastegate
A. Check the operation of the turbocharger wastegate.
B. Check the operation of the wastegate actuator. Refer to Systems Operation, Testing, and Adjusting, "Turbocharger - Inspect".
Turbocharger wastegate
Result: There is a suspected fault in the wastegate or the wastegate actuator.
Repair: Replace the turbocharger. Refer to Disassembly and Assembly, "Turbocharger - Remove" and Disassembly and Assembly, "Turbocharger - Install".
Result: The wastegate and the wastegate actuator operate correctly.
Proceed to Test Step 3.
3. Wastegate Regulator
A. Use the electronic service tool to check for diagnostic trouble codes that relate to the wastegate regulator.
Wastegate regulator
Result: Diagnostic codes are present that relate to the wastegate regulator.
Repair: Rectify the cause of any related codes. Refer to Troubleshooting, "Diagnostic Trouble Codes".
Result: There are no diagnostic codes that relate to the wastegate regulator.
Contact the Dealer Solution Network (DSN).