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P0020 Code Explained: “A” Camshaft Position Actuator Circuit Bank 2 Causes, Symptoms & Fixes

OBD-II scanner displaying P0020 beside a Bank 2 intake VVT solenoid, camshaft phaser, damaged wiring and Check Engine Light

If your OBD-II scanner displays P0020, your vehicle’s Engine Control Module (ECM) or Powertrain Control Module (PCM) has detected an electrical problem in the Bank 2 “A” camshaft position actuator circuit.

On most dual-overhead-cam engines, Camshaft A refers to the intake camshaft, while Bank 2 is the side of the engine opposite Bank 1. Bank 1 contains cylinder number one, so Bank 2 is the other cylinder bank.

The camshaft position actuator—often called a variable valve timing solenoid, VVT solenoid, oil control valve or camshaft timing control valve—regulates oil flow to the camshaft phaser. This allows the ECM to advance or retard intake camshaft timing according to engine speed, load, temperature and throttle position.

P0020 is usually caused by:

Unlike P0021 or P0022, which indicate that the camshaft timing is mechanically over-advanced or over-retarded, P0020 primarily indicates an electrical circuit fault.

The vehicle may continue to run, but the ECM may disable variable valve timing on Bank 2. This can cause reduced performance, rough running, poor fuel economy and increased emissions.

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P0020 Quick Facts

ItemInformation
OBD-II codeP0020
Official description“A” Camshaft Position Actuator Circuit Bank 2
CategoryPowertrain
SystemVariable valve timing
Code typeGeneric SAE powertrain code
SeverityModerate
Safe to drive?Usually for a limited distance
Most common causesFailed VVT solenoid, wiring damage, connector fault
Typical repair cost$100–$1,200+

What Does the P0020 Code Mean?

P0020 means “‘A’ Camshaft Position Actuator Circuit Bank 2.”

The ECM has detected an electrical problem in the circuit controlling the Bank 2 intake camshaft actuator.

The actuator circuit typically includes:

The ECM energizes the VVT solenoid using a duty-cycle-controlled electrical signal. The solenoid then directs pressurized engine oil to the camshaft phaser.

When the ECM detects that the circuit voltage, current or resistance is outside the expected range, it stores P0020.

The fault may be caused by:

P0020 is closely related to:

What Does Camshaft A Mean?

On most dual-overhead-cam engines:

Camshaft A controls when the intake valves open and close.

The Bank 2 intake camshaft actuator allows the ECM to adjust intake-valve timing for:

Manufacturer terminology can vary, so confirm Camshaft A using vehicle-specific service information before replacing components.

What Is Bank 2?

Bank 2 is the side of the engine that does not contain cylinder number one.

Bank 2 exists only on engines with multiple cylinder banks, including:

Inline engines normally have only one bank and should not store a true Bank 2 actuator code.

Depending on the manufacturer, Bank 2 may be located on either the driver or passenger side.

Confirm Bank 2 using:

Do not identify Bank 2 by guessing based on vehicle orientation.

How the Camshaft Position Actuator Works

The camshaft position actuator system uses engine oil pressure to change camshaft timing while the engine is running.

A typical system includes:

The process works as follows:

  1. The ECM calculates the desired camshaft angle.
  2. The ECM sends a duty-cycle command to the VVT solenoid.
  3. The solenoid opens or closes internal oil passages.
  4. Pressurized oil flows into the camshaft phaser.
  5. The phaser rotates the camshaft slightly relative to the timing chain.
  6. The camshaft position sensor reports the actual position.
  7. The ECM adjusts the command as needed.

If the actuator circuit is open or shorted, the ECM may lose control of the Bank 2 intake camshaft.

The system may then default to a fixed timing position.

How the ECM Detects P0020

The ECM monitors electrical activity in the VVT actuator circuit.

Depending on the system design, it may monitor:

P0020 may be stored when the ECM detects:

Some vehicles may store P0020 immediately after startup.

Others require the fault to occur during specific operating conditions.

Symptoms of the P0020 Code

The symptoms of P0020 vary depending on the engine and whether the actuator is stuck electrically or mechanically.

Common symptoms include:

Some vehicles may show no noticeable symptoms beyond the Check Engine Light.

The ECM may disable Bank 2 variable valve timing and operate the engine using a default camshaft position.

Common Causes of P0020

1. Failed Bank 2 Intake VVT Solenoid

A failed VVT solenoid is one of the most common causes of P0020.

The solenoid contains an electrical coil that moves an internal valve.

The coil may fail because of:

A failed solenoid may not respond when the ECM commands it.

The solenoid can also fail mechanically by sticking, although a purely mechanical fault may be more likely to produce P0021 or P0022.

2. Open Actuator Circuit

An open circuit prevents current from flowing through the solenoid.

Possible causes include:

An open circuit may cause infinite resistance when tested with a multimeter.

3. Short to Ground

A wire shorted to ground may cause excessive current flow or pull the control circuit permanently low.

Possible causes include:

A short to ground may cause:

4. Short to Voltage

A control circuit shorted to battery voltage may prevent the ECM from controlling the actuator properly.

Possible causes include:

A short to voltage may cause the solenoid to remain energized or produce an implausible circuit reading.

5. Damaged Wiring Harness

The actuator wiring may be damaged by:

Common damage locations include:

Intermittent wiring faults may appear only when the engine moves or reaches operating temperature.

6. Loose or Corroded Connector

A poor connector connection can create excessive resistance or an intermittent open circuit.

Inspect for:

A connector may look attached while its terminals are not making reliable contact.

7. Oil Inside the Electrical Connector

Engine oil can enter the VVT solenoid connector through:

Oil contamination may interfere with terminal contact and attract dirt.

Clean the connector using an appropriate electrical-contact cleaner and replace leaking components.

8. Blown Fuse or Failed Power Supply

Some VVT solenoids share a fused ignition-voltage supply with other engine-control components.

A blown fuse may affect:

If the fuse is blown, identify the short before replacing it.

Installing a larger fuse can damage the wiring or ECM.

9. High Resistance in the Circuit

The circuit may remain connected but have too much resistance.

Possible causes include:

Voltage-drop testing is often more useful than a basic continuity test for finding high-resistance faults.

10. Poor Engine or ECM Grounds

The ECM and actuator system depend on stable electrical grounds.

Poor grounds may be caused by:

Poor grounds may cause multiple unrelated electrical codes.

11. Low Battery Voltage

Low system voltage may interfere with actuator control and ECM monitoring.

Possible causes include:

Check battery and charging voltage if several actuator or circuit codes are stored together.

12. Contaminated or Sticking VVT Solenoid

Although P0020 is primarily electrical, oil contamination can contribute to solenoid failure.

The actuator may become contaminated by:

A sticking solenoid may draw abnormal current or fail to respond correctly.

13. Faulty ECM or PCM Driver

The ECM controls the VVT solenoid using an internal transistor driver.

The driver may fail because of:

ECM failure is uncommon and should only be suspected after verifying:

14. Incorrect Replacement Solenoid

An incorrect or low-quality replacement solenoid may have:

The part may physically fit while remaining electrically incompatible.

Use the correct part number for the engine and bank.

15. Previous Wiring Repairs

Improper repairs may create:

Inspect previous repairs carefully, especially if the code appeared after engine or collision work.

Is P0020 an Electrical or Mechanical Code?

P0020 is primarily an electrical circuit code.

It indicates that the ECM has detected a problem controlling or monitoring the Bank 2 intake camshaft actuator circuit.

This differs from:

However, electrical and mechanical problems can overlap.

For example:

Diagnose the electrical circuit first when P0020 is present.

How Serious Is the P0020 Code?

P0020 is generally considered moderately serious.

The engine will often continue running, but the ECM may disable variable valve timing on Bank 2.

Possible consequences include:

P0020 is less likely than a correlation code to indicate immediate timing-chain failure, but it should still be repaired promptly.

The problem becomes more urgent if accompanied by:

Can You Drive With P0020?

Limited driving is often possible if:

However, continued driving is not recommended.

Stop driving if:

A shorted actuator circuit can potentially damage the ECM or wiring harness.

How to Diagnose P0020

Step 1: Scan for Additional Codes

Use an OBD-II scanner to check for related codes.

Common companion codes include:

Record:

Do not clear the code before saving this information.

Step 2: Confirm Bank 2 and Camshaft A

Use service information to identify:

Do not guess based on the physical location of the solenoid.

Step 3: Check Battery and Charging Voltage

Measure battery voltage before advanced diagnosis.

Typical readings are approximately:

Actual acceptable voltage varies by vehicle.

Low voltage can cause multiple actuator and circuit codes.

Step 4: Inspect the Engine Oil

Although P0020 is an electrical code, inspect:

Dirty oil may damage or stick the actuator.

Correct oil problems before completing the repair.

Step 5: Perform a Visual Wiring Inspection

Inspect the actuator harness for:

Move the harness gently while monitoring scan data or circuit continuity.

An intermittent fault may appear during a wiggle test.

Step 6: Inspect the Connector

Disconnect the actuator connector with the ignition off.

Inspect for:

Verify that each terminal grips the matching pin correctly.

Step 7: Measure Solenoid Resistance

Use a digital multimeter to measure resistance across the solenoid terminals.

Compare the reading with manufacturer specifications.

Possible results include:

A solenoid can pass a resistance test and still fail mechanically or intermittently.

Step 8: Check the Power Supply

Turn the ignition on and test the actuator power-supply terminal.

Depending on the system, the solenoid may receive:

If voltage is missing, inspect:

Do not replace the solenoid if its power supply is missing.

Step 9: Test the ECM Control Circuit

The ECM commonly controls the solenoid by pulsing the ground side of the circuit.

Test for:

Use wiring diagrams and manufacturer procedures.

Avoid applying battery voltage directly to an ECM control wire.

Step 10: Perform Voltage-Drop Testing

A circuit may pass a continuity test while failing under load.

Perform voltage-drop testing across:

Excessive voltage drop indicates resistance in the circuit.

Voltage-drop specifications vary, but lower readings are generally better.

Step 11: Command the Solenoid With a Scan Tool

A bidirectional scan tool may allow the technician to command the Bank 2 intake VVT solenoid.

Monitor:

If the ECM commands the solenoid but no electrical activity occurs, suspect:

If electrical activity is present but camshaft timing does not change, suspect:

Step 12: Use an Oscilloscope or Current Probe

An oscilloscope can display the ECM’s pulse-width-modulated control signal.

A current probe can help identify:

This level of testing is especially useful when P0020 is intermittent.

Step 13: Bench-Test the Solenoid

If permitted by the manufacturer, remove and bench-test the solenoid.

Inspect for:

Use a fused power source and follow manufacturer testing procedures.

Do not energize the solenoid longer than recommended.

Step 14: Compare Bank 1 and Bank 2 Solenoids

If the engine uses identical intake VVT solenoids on both banks, compare:

Some technicians temporarily swap identical solenoids between banks to see whether the code follows the component.

Only do this when:

If the code moves to Bank 1, the solenoid is likely defective.

Step 15: Inspect the ECM Connector

If the solenoid and wiring test correctly, inspect the ECM connector.

Look for:

Disconnect the battery or follow manufacturer power-down procedures before unplugging the ECM.

Step 16: Test the ECM Driver

Only suspect the ECM driver after verifying:

A professional scan tool or oscilloscope may confirm that the ECM is not providing the expected control signal.

Before replacing the ECM, check for manufacturer service bulletins and software updates.

Step 17: Verify the Repair

After completing repairs:

  1. Clear all stored codes.
  2. Start the engine.
  3. Command the actuator with a scan tool if possible.
  4. Monitor Bank 2 intake camshaft position.
  5. Inspect for oil leaks.
  6. Complete the required drive cycle.
  7. Rescan for pending codes.
  8. Restart the engine several times.

A successful repair should restore actuator control and prevent P0020 from returning.

Common P0020 Repairs and Costs

RepairEstimated cost
Diagnostic inspection$100–$250
Engine oil and filter change$60–$180
Clean electrical connector$50–$150
Replace VVT connector$75–$300
Repair actuator wiring$100–$600
Replace fuse or relay$50–$250
Replace Bank 2 intake VVT solenoid$150–$500
Clean VVT oil passages$150–$600
Replace camshaft phaser$600–$1,800
Replace engine wiring harness$800–$2,500+
ECM software update$100–$300
Replace and program ECM$1,000–$2,500+

Repair costs vary depending on:

Many P0020 repairs involve the solenoid, connector or wiring and do not require engine disassembly.

Common Diagnostic Mistakes

Replacing the Camshaft Position Sensor

P0020 refers to the camshaft actuator circuit, not necessarily the camshaft position sensor.

The actuator and position sensor are different components.

Confusing P0020 With P0018

P0020 is an electrical actuator-circuit code.

P0018 is a crankshaft-to-camshaft correlation code.

Confusing P0020 With P0021 or P0022

P0021 means Bank 2 intake camshaft timing is over-advanced.

P0022 means Bank 2 intake camshaft timing is over-retarded.

P0020 means the actuator’s electrical circuit has a fault.

Replacing the Solenoid Without Testing the Wiring

A new solenoid will not fix:

Test the circuit first.

Checking Continuity but Skipping Voltage Drop

A wire with only a few intact strands may pass a continuity test but fail when current flows.

Voltage-drop testing can reveal resistance that a basic continuity test misses.

Ignoring Oil Inside the Connector

Oil contamination can cause poor terminal contact and repeated electrical faults.

The source of the oil must also be repaired.

Replacing a Blown Fuse Without Finding the Short

A blown fuse is a symptom.

Identify and repair the short before installing another fuse.

Confusing Bank 1 and Bank 2

Bank 1 contains cylinder number one.

Bank 2 is the opposite bank.

Testing the wrong solenoid can lead to unnecessary parts replacement.

Confusing Intake and Exhaust Solenoids

Camshaft A usually refers to the intake camshaft.

Camshaft B usually refers to the exhaust camshaft.

Confirm the correct solenoid before disconnecting or replacing it.

Applying Battery Voltage to the ECM Circuit

Applying voltage directly to the wrong terminal can damage the ECM.

Use the wiring diagram and follow manufacturer test procedures.

Replacing the ECM Too Early

ECM failure is uncommon compared with:

Verify the entire circuit before replacing the module.

Vehicles Commonly Affected by P0020

P0020 may appear on OBD-II vehicles equipped with multiple cylinder banks and intake variable valve timing.

Potentially affected manufacturers include:

P0020 is commonly associated with engines using:

The code alone does not prove that a particular vehicle has a known defect.

Diagnosis must be based on:

How to Prevent P0020

Helpful preventive measures include:

Routine oil maintenance helps protect the actuator mechanically, while regular visual inspections help prevent electrical circuit faults.

Frequently Asked Questions About P0020

What does code P0020 mean?

P0020 means the ECM has detected an electrical problem in the Bank 2 intake camshaft actuator circuit.

Is Camshaft A the intake camshaft?

On most engines, yes.

Camshaft A usually refers to the intake camshaft.

Which side is Bank 2?

Bank 2 is the side of the engine that does not contain cylinder number one.

Its physical location varies by manufacturer.

Is the camshaft actuator the same as the VVT solenoid?

Usually, yes.

The component may also be called:

Is P0020 an electrical code?

Yes. P0020 primarily identifies a fault in the electrical circuit controlling the Bank 2 intake camshaft actuator.

Can low oil cause P0020?

Low oil is more likely to cause a timing-performance code than a direct circuit code.

However, poor oil maintenance can damage or contaminate the actuator and contribute to failure.

Can dirty oil cause P0020?

Dirty oil may cause the actuator to stick or overheat, but P0020 usually indicates an electrical fault such as a failed coil, open circuit or short.

Can a bad VVT solenoid cause P0020?

Yes. A failed Bank 2 intake VVT solenoid is one of the most common causes.

Can damaged wiring cause P0020?

Yes. Broken, shorted, corroded or high-resistance wiring can trigger P0020.

Can a bad camshaft sensor cause P0020?

Usually not directly.

P0020 refers to the actuator circuit, while a camshaft sensor fault generally stores a separate position-sensor code.

Can a blown fuse cause P0020?

Yes. A blown fuse may remove power from the VVT solenoid circuit.

The cause of the blown fuse must be identified.

Can a weak battery cause P0020?

Low voltage can contribute to actuator circuit faults, especially if several voltage-related codes are stored.

Can a bad ECM cause P0020?

Yes, but ECM failure is uncommon.

The solenoid, wiring, connector, power supply and grounds should be tested first.

Can I drive with P0020?

Limited driving may be possible if the engine runs normally and the Check Engine Light remains steady.

Prompt repair is still recommended because the engine may lose variable valve timing operation.

Can P0020 cause rough idle?

Yes. Disabled or incorrect intake camshaft control may cause rough idle and hesitation.

Can P0020 cause poor acceleration?

Yes. The engine may lose low-speed torque or high-RPM power when variable valve timing is disabled.

Will an oil change fix P0020?

Usually not if the fault is electrical.

An oil change may help if the solenoid is contaminated, but it will not repair a failed coil, broken wire or damaged ECM driver.

How much does it cost to fix P0020?

A wiring or connector repair may cost $100 to $600.

A VVT solenoid replacement commonly costs $150 to $500.

ECM or wiring-harness repairs can exceed $1,000.

Will clearing P0020 fix the vehicle?

No. Clearing the code only turns off the warning temporarily.

The code will return if the circuit fault remains.

Will P0020 fail an emissions test?

Yes. An active Check Engine Light or emissions-related powertrain code will generally cause an OBD-based emissions inspection failure.

Final Thoughts

The P0020 code means the ECM has detected an electrical fault in the Bank 2 intake camshaft actuator circuit.

The most common causes include:

Begin diagnosis by identifying Bank 2 and Camshaft A using vehicle-specific service information.

Inspect the actuator connector and wiring, test solenoid resistance, verify the power supply and check the ECM control circuit. Use voltage-drop testing to locate hidden resistance and a bidirectional scan tool to command the actuator when possible.

Do not replace the camshaft position sensor simply because the word “camshaft” appears in the code description. P0020 refers specifically to the actuator control circuit.

Addressing the problem promptly can restore variable valve timing, improve engine performance and prevent additional electrical or drivability problems.

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