HomeTrouble CodesP2090

P2090 — B Camshaft Position Actuator Control Circuit Low Bank 1

Manufacturer-specificPowertrain (engine & transmission)

P2090 indicates a low voltage condition in the camshaft position actuator control circuit for bank 1, meaning the PCM is detecting insufficient voltage to operate the camshaft actuator motor.

Symptoms

What causes it — most likely first

1. Faulty camshaft position actuator motor (B) on bank 1

The actuator motor that advances or retards cam timing can develop internal winding failures, causing a low voltage reading.

2. Open or high‑resistance wiring/connector in the actuator control circuit

Corroded pins, broken wires, or loose connectors can drop voltage before it reaches the actuator.

3. Failed camshaft position sensor (bank 1) providing incorrect feedback

If the sensor signals out‑of‑range data, the PCM may limit voltage to protect the actuator.

4. Defective PCM output driver for the actuator control circuit

A rare internal failure in the PCM can prevent proper voltage delivery, but this is far less common than mechanical or wiring issues.

How it's diagnosed

  1. Verify the code with a live data scan and confirm low voltage on the actuator control circuit while the engine is running.
  2. Inspect the wiring harness and connectors between the PCM and the bank 1 camshaft actuator for damage, corrosion, or looseness.
  3. Measure resistance of the actuator motor windings; replace the motor if resistance is out of specification.
  4. Test the camshaft position sensor signal for proper frequency and voltage; replace the sensor if it is out of range.
  5. If all hardware checks are normal, perform a PCM output driver test or substitute a known‑good PCM to rule out internal PCM failure.

Code facts & related codes

SystemPowertrain (engine & transmission)
StandardizationManufacturer-specific (P1/B1/C1/U1)

Frequently asked

Do I need to replace the PCM for a P2090 code?

In most cases no. The PCM is rarely at fault; the problem is usually a bad actuator, wiring, or sensor. Replacing the PCM should be a last‑resort after all other components have been verified.

Can a simple battery voltage drop cause P2090?

A weak battery can produce low system voltage, but the PCM monitors the specific actuator circuit voltage. If the battery is low, it will usually set a different code. Still, ensure the battery is fully charged before diagnosing.

Will resetting the code clear the problem?

Clearing the code only turns off the MIL temporarily. If the underlying fault remains, the code will return after a few drive cycles.

Is it safe to drive with a P2090 code active?

Driving is possible but performance may be reduced and fuel economy will suffer. Prolonged operation can lead to additional wear on the camshaft actuator and may cause the engine to run out of timing, so repair should be scheduled promptly.