P001A–P002D A Camshaft Profile Actuator A Control Circuit/Open Bank 1
The circuit is broken somewhere - a cut wire, a corroded pin or an unplugged connector means the signal never arrives.
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 |
|---|---|---|
P001A | A Camshaft Profile Actuator A Control Circuit/Open Bank 1 | Investigate soon |
P001D | A Camshaft Profile Actuator A Control Circuit/Open Bank 2 | Investigate soon |
P002A | B Camshaft Profile Actuator A Control Circuit/Open Bank 1 | Investigate soon |
P002D | B Camshaft Profile Actuator A Control Circuit/Open Bank 2 | Investigate soon |
The definition
P001A: A Camshaft Profile Actuator A Control Circuit/Open Bank 1.
P001A 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:
- Check the connector is fully seated and the locking tab is engaged. A half-seated plug is the single most common cause of an open circuit.
- Back-probe the pins and check continuity from the part back to the module connector.
- Inspect for a pushed-back or corroded terminal - the wire looks fine but the pin has backed out of the housing.
What actually causes this on a VAG
Several VAG petrol engines use a system that switches the camshaft between two different lobe profiles - a small one for economy and smooth running, a bigger one for power. Small electrical actuators on the cylinder head push a pin out to slide the cam sleeve across. This code says the engine control unit cannot see actuator A on bank one at all: the circuit reads as broken or open. The engine will usually still run, but it will be stuck on one profile, so it may feel flat, or rough at certain revs.
Most likely causes, in order
- Connector unplugged or damaged after recent work. These actuators sit on top of the engine among the coil packs and the cam cover, so they are routinely knocked or left unclipped during spark plug, coil or cover work. If the code appeared soon after anything was done to the top of the engine, unclip and firmly reseat the connector on that actuator and clear the code before spending anything. Check the little locking clip has actually engaged rather than just resting in place.
- Oil-contaminated or corroded connector pins. Oil mist creeps along the wiring and into the plug in this area, and it wicks between the terminals over time. Pull the plug and look inside: oily, green or spread terminals give an intermittent or open connection that behaves exactly like a broken wire. Clean with electrical contact cleaner and check the terminals grip a probe firmly rather than flopping about.
- The actuator solenoid has failed internally open. The winding inside can go open circuit with heat cycling. If your engine has more than one of these actuators and they are genuinely the same part - check the numbers moulded on them match before you touch anything, because neighbouring positions are not always interchangeable - the cheapest confirmation is a swap test: move the suspect actuator to another position, clear the codes and drive. If the fault moves with it, the actuator is at fault; if it stays put, the problem is in the wiring or the control unit.
- Chafed wiring in the engine loom. The loom runs across a hot, vibrating engine, and a wire rubbed through against a bracket or a heat shield gives the same open circuit as a dead actuator. Follow the wires back from the actuator with the loom flexed by hand, looking for shiny, cracked or melted insulation, particularly where the harness crosses a hard edge.
Worth knowing: This is an electrical fault code, not a mechanical one - it says the control unit has lost the circuit, not that the camshaft mechanism itself is broken. With an open circuit the actuator cannot be energised at all, so the pin simply stays where it is; the consequence is that the engine is locked on one cam profile, not that something is grinding itself apart. That is worth knowing before anyone quotes you for camshaft work off the back of this code. It still wants fixing rather than living with, because running permanently on one profile is not what the engine was calibrated for, and it will keep the light on and fail an emissions test.
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.
$249 once. No subscription, unlimited cars. Windows 10/11.
See VAGPULSE — $249 Look up another codeSoftware downloads instantly · cable ships September 30 · cable guarantee — refund if it won't connect
Prefer to work on your phone? The VAGPULSE Android app is a free download and its demo mode runs against a sample car with no hardware at all, so you can see exactly what it reads before spending anything. Reading your car with it needs the VAGPULSE cable, which comes with the licence.
Common questions
What does P001A mean?
P001A means A Camshaft Profile Actuator A Control Circuit/Open Bank 1. The circuit is broken somewhere - a cut wire, a corroded pin or an unplugged connector means the signal never arrives.
Can I drive with P001A?
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.