P2B46 code meaning
A Camshaft Position Actuator Position Sensor B Circuit High Bank 2
Powertrain system Generic code P2Bxx codes Check engine light
What P2B46 means
P2B46 flags a signal from position sensor B on the bank 2 intake camshaft actuator that is stuck too high. Most often the sensor has lost its ground, the signal line has contact with a supply line, or the sensor element itself has failed. There is no public manufacturer description of P2B46; NTN-SNR lists it simply as inlet sensor B, second bank, signal too high. On engines like the Mercedes M176/M177, whose CAMTRONIC actuators have the sensor built in, replacing the actuator is the usual repair once the wiring checks out. With the feedback lost, the engine control keeps the cam lift in its default position, so drivers mostly notice the warning lamp and a little more fuel use. Bank 1 counterpart: P2B42.
P2B46 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 3.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2B46
- Check engine light on
- Cam lift held in default position on bank 2
- Slightly increased fuel consumption
Common causes of P2B46
- Most likelySensor ground interrupted
- PossibleSignal line in contact with a supply line
- PossibleSensor element in the actuator failed
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
A camshaft position actuator pos sensor b b2Wiring harnessECM
What each part of P2B46 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| B | Area: hybrid propulsion. |
| 46 | The exact fault in that area. |
What to do next
- Note P2B46 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 P2B46
What does P2B46 mean?
P2B46 means "A Camshaft Position Actuator Position Sensor B Circuit High Bank 2". P2B46 flags a signal from position sensor B on the bank 2 intake camshaft actuator that is stuck too high. It is a generic code, so it means the same on every make.
Is it safe to drive with P2B46?
Drive gently and only to a workshop. With P2B46 the car can go into limp mode (reduced power) to protect itself.
Will P2B46 fail an emissions test?
Yes, it can. P2B46 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 P2B46 to fix?
Difficulty: medium. A typical repair takes 0.5 to 3.5 hours of work. This is a job for a workshop.
Will P2B46 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.