Powertrain, generic (extended)

P22CB Turbocharger Compressor Outlet Switching Valve Control Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P22CB is set when the control line of the compressor outlet switching valve shows too little voltage for the present command, most often because the wire or the solenoid has a short to ground. On a low-side driven solenoid such a short can hold the valve energized all the time, so the outlet flap it supplies with vacuum or pressure stays in its switched position whatever the rpm and load. The module spots the fault through its driver diagnostics without any special driving. The solenoid is a small part in the actuating line of the outlet flap and is usually inexpensive; the wiring near the hot turbo area deserves a careful look. No manufacturer publicly documents P22CB. If P22C6 is present as well, look for a shared harness section or connector.

Likely causes

Control wire chafed and shorted to ground
Internal short in the switching solenoid
Water or corrosion in the solenoid connector

Symptoms

  • Check engine light on
  • Boost path stuck in one mode, uneven power across the rev range
  • Reduced power at low or high engine speed

Repair estimate

DifficultyEasyDIY possible
Parts and labour€30–300
Time0.3–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

boost switching valve

Related codes

P22CAP22CCP22C6

References: law.cornell.edu, patents.google.com, static.nhtsa.gov.