17964/P1556 - Charge Pressure Control: Negative Deviation
Possible Symptoms
Reduced power output
Limp mode
Possible Causes
Boost Pressure too Low
Hoses/Pipes incorrect connected, disconnected or leaking
Charger Pressure Control defective
VNT (variable nozzle turbo): nozzles stuck
Solenoid Valve for Boost Pressure Control (N75) defective
Possible Solutions
Check Hoses/Pipes to/between Components
Check Solenoid Valve for Boost Pressure Control (N75)
Check / Clean / Replace Charge Pressure Control
Check / Clean mechanism for variable nozzles
