P2090: Camshaft actuator B control circuit low (bank 1)
The ECU sees a voltage below normal in the variable valve timing control on the exhaust side. It is usually wiring, a connector or the solenoid.
| Code | P2090 |
|---|---|
| System | Engine and transmission |
| Group | P20xx, Emissions: catalysts and AdBlue |
| Type | Generic: it means the same on every make |
| Can you keep driving? | With care |
What P2090 means
Many engines turn the camshaft slightly to adjust valve timing as you drive, using a solenoid controlled by the ECU. This code means the electrical signal for that solenoid (actuator B, usually the exhaust camshaft) on bank 1 is below what it should be. It is almost always an electrical fault. Which camshaft counts as B is up to each manufacturer.
Most common causes
- Loose, dirty or corroded connector on the camshaft solenoid
- A wire in the circuit chafed through or shorted to ground
- The variable valve timing solenoid itself, with a failed coil
- Very dirty oil or a low oil level making the solenoid work poorly
- A fault in the engine ECU, which is uncommon
Symptoms
- Engine warning light on
- Rough idle or some loss of power
- Slightly higher fuel consumption
- The engine may go into limp mode
Can you drive with P2090?
With care You can drive, as the ECU usually locks the timing in a fixed position. The engine will be down on power, so have it checked soon.
Open the bonnetthe in-depth explanation
How to check it
Check the oil level and condition first. With the engine off, make sure the solenoid connector is fully seated and free of green corrosion.
How to read and clear P2090 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P2090 with its description and whether it’s confirmed, pending or permanent.
If the engine stores it over standard OBD, with FREE you read this code with its explanation for nothing and clear it. With PRO you also read the faults of every control unit and clear them in all of them.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- P208C The AdBlue pump control gives a lower signal than normal
- P208D The AdBlue pump control gives a higher signal than normal
- P208E The AdBlue injector is stuck closed
- P208F AdBlue injector 1 on bank 2 is stuck closed
- P2091 Camshaft actuator B control circuit high (bank 1)
- P2092 The camshaft actuator A circuit on bank 2 has a low signal
- P2093 The camshaft actuator A circuit on bank 2 has a high signal
- P2094 The camshaft actuator B circuit on bank 2 has a low signal
- P2002 Diesel particulate filter efficiency below threshold (bank 1)
- P2003 Diesel particulate filter efficiency below threshold (bank 2)
- P2004 Intake manifold runner control stuck open (bank 1)
- P2005 Intake manifold runner control stuck open (bank 2)
What does code P2090 mean?
Many engines turn the camshaft slightly to adjust valve timing as you drive, using a solenoid controlled by the ECU. This code means the electrical signal for that solenoid (actuator B, usually the exhaust camshaft) on bank 1 is below what it should be. It is almost always an electrical fault. Which camshaft counts as B is up to each manufacturer.
Can you drive with P2090?
You can drive, as the ECU usually locks the timing in a fixed position. The engine will be down on power, so have it checked soon.
How do you clear P2090?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, P2090 comes back.
Read it on your car
Final OBD reads and clears engine faults through standard OBD for free, each one explained in plain English. With PRO it also reads the faults of every control unit, each make’s own codes included, and clears them in all of them.
