Engine

P001B — Camshaft Profile Control Circuit Low (Bank 1)

Severity: medium Drive with care, to a shop

What P001B means

The engine control unit adjusts camshaft profile (valve timing or lift) using a solenoid or actuator that works with oil pressure. P001B sets when the voltage in this control circuit on Bank 1 is lower than expected. This points to an electrical problem such as an open circuit, a short to ground or a failing solenoid.

Symptoms

  • Check engine light on
  • Reduced power
  • Rough idle
  • Hesitation when accelerating
  • Worse fuel economy
  • Inconsistent throttle response

Possible causes

  1. Faulty camshaft profile control solenoid or actuator
  2. Damaged wiring or corroded connector pins
  3. Control wire shorted to ground
  4. Low or dirty engine oil affecting variable valve operation
  5. PCM failure (uncommon)

How to diagnose

  1. Read all codes and freeze frame data, then clear the code and see if it returns
  2. Check oil level, condition and that it matches the manufacturer's spec
  3. Inspect the Bank 1 solenoid wiring and connector for chafing, oil intrusion and corrosion
  4. Measure the solenoid coil resistance and compare it to specifications
  5. Test the power and control circuits for opens and shorts to ground
  6. Run a scan tool actuator test and watch the solenoid response
  7. If wiring and solenoid are good, check the PCM and look for software updates

Common fixes

  • Replace the camshaft profile control solenoid or actuator
  • Repair the wiring or replace the connector
  • Change the oil and filter with the correct grade
  • Reprogram or replace the PCM (last resort)

Questions and answers

What does P001B mean?

It means low voltage in the camshaft "A" profile control circuit on Bank 1. The usual culprits are the solenoid, wiring or connector.

Can I drive with P001B?

Briefly, yes, but the engine may lose power and idle roughly. Have it diagnosed soon.

Can bad oil cause P001B?

Oil affects how the system works, but this code points to the electrical circuit. Check the wiring and solenoid as well as the oil.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.