P022C–P022F Charge Air Cooler Bypass Control A Circuit High
The voltage on this circuit is sitting near battery voltage. Typically a short to a positive feed, or a disconnected sensor floating high.
Can you drive it? The engine light will stay on and the car may run in a reduced-power mode. Read the freeze-frame data to see the conditions the fault was logged under.
Which code is which
Same fault, different cylinder or bank — diagnosed the same way. Several set together usually means one shared cause.
| Code | Definition | Severity |
|---|---|---|
P022C | Charge Air Cooler Bypass Control A Circuit High | Investigate soon |
P022F | Charge Air Cooler Bypass Control B Circuit High | Investigate soon |
The definition
P022C: Charge Air Cooler Bypass Control A Circuit High.
P022C is a powertrain code (the engine or gearbox), defined by the SAE standard - it means the same thing on any make of car, and any generic OBD-II reader will decode it.
What to check first
Cheapest and fastest checks first:
- Unplug the sensor and check whether the signal falls. If it stays high, suspect the wiring rather than the sensor.
- Check the earth path - a missing earth makes a sensor read high.
What actually causes this on a VAG
P022C is an electrical fault on the ECU output that drives a charge air cooler bypass - a valve or flap that lets the charge air, or the coolant that cools it, go around the intercooler while the engine is warming up and cooling is not wanted. Only certain engines are built with one, so this is an uncommon code rather than a routine VAG failure, and the hardware differs between engine families. "Circuit high" describes what the ECU measured on its own output, not the condition of the cooler: on an actuator circuit it normally means the circuit is open, or is seeing battery voltage where it should not. It is an electrical complaint, not a statement that anything has overheated.
Most likely causes, in order
- Connector or wiring at the actuator. By far the most common cause of a circuit-high on any actuator: a plug not fully latched, spread or green pins, moisture in the connector, or a chafed section of loom. These parts sit in the engine bay where heat cycling and vibration work connectors loose. Unplug it, look at the pins, and wiggle the loom while watching the fault status in live data.
- The control valve or flap actuator itself. An internal break in the actuator's winding reads to the ECU exactly like a disconnected plug. With the connector off, a healthy solenoid reads a low but definite resistance across its terminals, while an open-circuit reading points at the actuator rather than the loom. Compare against the figure given for your specific engine rather than a number from a forum, as these vary.
- The ECU output driver. Rare, and only worth considering once the connector, the loom and the actuator have all been checked and proved good. Do not let this be the first thing replaced.
Worth knowing: Read the car with a VAG-capable tool before ordering anything, because it will name the exact component the manufacturer means on your engine - a generic reader only gives you the SAE wording. And because this actuator is only commanded under particular conditions, typically during warm-up, the fault can look intermittent and simply clearing it can seem to fix it. After any repair, clear the code, then run the car through a full cold start to fully warm before re-reading. That cycle is what proves the repair, and it stops you chasing a fault that was fixed two parts ago.
Reading the code is the easy part
A code names the circuit that complained. What tells you why is watching the sensor behind it while the engine runs — and that is where a code reader stops and a diagnostic tool starts.
VAGPULSE reads every module in a VW, Audi, Skoda or SEAT — not just the engine — shows the live measuring blocks behind this fault, gives you the freeze-frame conditions it was logged under, and clears it once you have fixed it. It also does what a generic OBD reader cannot on a VAG: service resets, coding, adaptations, and Stage 1–3 flashing with your original file saved first.
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Common questions
What does P022C mean?
P022C means Charge Air Cooler Bypass Control A Circuit High. The voltage on this circuit is sitting near battery voltage. Typically a short to a positive feed, or a disconnected sensor floating high.
Can I drive with P022C?
The engine light will stay on and the car may run in a reduced-power mode. Read the freeze-frame data to see the conditions the fault was logged under.