P001B code meaning
A Camshaft Profile Actuator A Control Circuit Low Bank 1
Powertrain system Generic code P00xx codes Check engine light
What P001B means
A camshaft profile actuator switches the intake camshaft (camshaft A) on bank 1 between two or more fixed cam profiles with different valve lift and duration, for example by shifting a cam piece axially or by locking rocker arms or tappets with oil pressure. Unlike a camshaft phaser it does not shift the timing continuously. The second letter "A" in the title numbers the actuator on this camshaft. This code is set when the control circuit reads too low, typically because the control wire is shorted to ground. The engine usually stays on one profile, typically the base profile with low lift. Some manufacturers report these faults with their own codes instead.
P001B at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2.5 hours
- Clears after repairAfter a drive cycle
Symptoms of P001B
- Check engine light on
- Less power at high engine speed because the profile does not switch
- Higher consumption or uneven part-load running, depending on the profile
- Engine speed may be limited
Common causes of P001B
- Most likelyControl wire chafed through and shorted to ground
- PossibleConnector corroded or contaminated with oil
- PossibleShorted turns in the actuator coil
- Less likelyOutput driver in the engine control module faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Camshaft profile actuator intake bank1Camshaft profile actuator wiringEngine control module
What each part of P001B means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 0 | Area: fuel and air metering and auxiliary emission controls. |
| 1B | The exact fault in that area. |
What to do next
- Note P001B and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P001B
What does P001B mean?
P001B means "A Camshaft Profile Actuator A Control Circuit Low Bank 1". A camshaft profile actuator switches the intake camshaft (camshaft A) on bank 1 between two or more fixed cam profiles with different valve lift and duration, for example by shifting a cam piece axially or by locking rocker arms or tappets with oil pressure. It is a generic code, so it means the same on every make.
Is it safe to drive with P001B?
Drive gently and only to a workshop. With P001B the car can go into limp mode (reduced power) to protect itself.
Will P001B fail an emissions test?
Yes, it can. P001B is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P001B to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P001B clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.