Fault code 462c

[veedub76]

Hi,
My wife's passats turbo has been cutting out and we've had a scan done and the code is 462C and it came up with 'Boost pressure control below limit'

Can anyone tell me if this is a serious problem relating to turbo charger or is it the thrust sensor etc etc??

Any help appreciated

[veedub76]

Think the code can also be interpreted as 17964???

[passat 130 tdi]

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

when you say cutting out , do you mean its been going to limp mode ???? or is it stalling all together?

[martin1810]

Check that none of the fat tubo pipes is split or undone. Check that the turbo actuator lever moves about 20mm when you start up. If it doesn't replace all the little vacuum pipes.

[veedub76]

Thanks for your suggestions. It's been going into limp mode and the turbo has been cutting out.

Have been told maybe the MAP sensor or N75 valve. Will check the actuator rod tomorrow, it feels a bit stiff. Is this something that has to be accessed from under the car on the B5 passats.??

Cheers

[martin1810]

You don't need to touch it. Just watch to see it move when someone else starts the car. Faulty MAF doesn't usually give your fault code. N75 valves rarely go wrong. Far more likely to be a faulty intercooler hose (the fat hoses) or a faulty vacuum hose (the little thin hoses). The MAP sensor is more likely to fail than the N75 valve.

[passat 130 tdi]

from my experience it was the MAP that failed £49 at dealers , but my new blue and red silicone hoses do look pretty .

id think low turbo pressure was maybe more down to a holed pipe as martin says , martin helped me with my faults for 3 days , i plagued the life outa the poor man - he-he. but he loves helping folks with mending the cars as do i .