01 You Could Destroy Your Entire Engine If You Keep Repeating … • 02 Best Toyota Hiace Diesel Engine: 1KD vs 2KD • 03 P0420 Code Explained: Catalyst System Efficiency Below Thre… • 04 B0041 - Left Front or Driver Side Deployment Loop Open • 05 P0024 B camshaft position - timing over advanced or system … • 06 iStop: The Revolutionary Brake-Activated Auto Stop-Start Sy… • 07 People Are Shocked To Learn This “Normal” Driving Action Ca… • 08 The Secret to a Long-Lasting Engine: It's Not Just Spark, A… • 09 Ways to Avoid Knocking in an SI Engine When the Compression… • 10 This Rolls-Royce Has An Umbrella That Dries Itself Inside T… •

DTC codes / BMW codes / P1529

P1529 · BMWB Camshaft Position Actuator Control Circuit Signal Low Bank 1

P1529 on a BMW indicates that the engine control module has detected a low signal voltage on the control circuit for the Bank 1 B camshaft position actuator, which is the variable valve timing solenoid that adjusts the intake or exhaust camshaft depending on engine design. The circuit is expected to carry a specific voltage when the actuator is commanded, and a low signal means the control wire is shorted to ground, the actuator coil has failed, or the wiring has excessive resistance.

SystemPowertrain
Code typeBMW specific
SeverityMedium
Fix difficultyIntermediate
AreaVehicle speed, idle control and auxiliary inputs

Symptoms you may notice

  • Illumination of the check engine light, often with no other noticeable symptoms
  • Rough idle or unstable engine speed, especially when cold
  • Reduced engine power or sluggish acceleration due to incorrect camshaft timing
  • Poor fuel economy or increased emissions
  • Occasional engine misfire or hesitation during light throttle
  • In some cases, the engine may enter limp mode with reduced performance

Common causes, most likely first

  1. Faulty Bank 1 B camshaft position actuator solenoid (open or shorted coil)
  2. Damaged or chafed wiring harness between the actuator and the engine control module
  3. Corroded or loose electrical connector at the actuator
  4. Short to ground in the control circuit wiring
  5. Failed engine control module driver for the actuator circuit (rare)
  6. Oil sludge or debris blocking the actuator oil passages, causing mechanical binding and abnormal current draw

How to diagnose and fix it

  1. Scan all modules for stored and pending codes, and record freeze-frame data to confirm the fault conditions
  2. Visually inspect the actuator connector and wiring for damage, corrosion, or loose pins
  3. Measure the resistance of the actuator solenoid with a multimeter and compare to BMW specifications
  4. Check for short to ground and continuity on the control circuit between the actuator and the engine control module
  5. Test the actuator with a bidirectional scan tool to command it on and off while monitoring signal voltage
  6. If electrical tests pass, remove the actuator and inspect for sludge or mechanical binding; clean or replace as needed
  7. Clear codes and perform a road test to verify the repair, and recheck for pending codes

Before you replace the camshaft actuator

  • A low signal code often results from a shorted actuator coil, but a chafed wire harness near the exhaust manifold or valve cover can mimic the same fault and is frequently overlooked.
  • Oil sludge or debris in the actuator oil passages can cause the solenoid to bind and draw excessive current, setting a low signal code even when the electrical circuit tests good.
  • The B camshaft actuator on some BMW engines controls the exhaust camshaft, so a fault can affect exhaust gas recirculation and emissions without obvious driveability symptoms.
  • After replacing the actuator, always clear adaptations and perform a camshaft position learn procedure if required, otherwise the code may return immediately.
  • A failing engine control module driver is rare, but a shorted actuator can damage the driver; always check for a short before installing a new module.

Can I keep driving with P1529?

You can usually drive the vehicle short distances to a repair shop, but avoid heavy acceleration or sustained high speeds because incorrect camshaft timing can cause poor performance and increased emissions. If the engine runs roughly or enters limp mode, stop driving and have the vehicle towed to prevent further damage.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for BMW vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage