B1606 BMW Fault Code
Check B1606 OBD Fault Code ReasonVariable Cam Timing Over-advanced (Bank 1) The comprehensive component monitor (CCM) monitors the VCT position for an over-advanced camshaft timing.
The test fails when the camshaft timing exceeds a maximum calibrated value or remains in an advanced position.
BMW cam timing improperly set No oil flow to the VCT piston chamber Low oil pressure VCT solenoid valve stuck closed Camshaft advance mechanism binding (VCT unit) B1606 DTC is a check of the VCT unit.
B1606 Code Symptoms :
The original multi-displacement system turned off opposite pairs of cylinders, allowing the engine to have three different configurations and displacements. B1606 code had an elaborate diagnostics procedure, including showing engine trouble codes on the air conditionning display. However, the system was troublesome, misunderstood by customers, and a rash of unpredictable failures led to the technology being quickly retired.
Diagnosis And Repairing B1606
B1606 OBD2 specifically refers to the camshaft (cam) timing. In this case, if the cam timing is over-retarded, the engine light will be illluminated and the code will be set.
How to fix B1606 code ?
- Erratic camshaft position due to low oil pressure
- Faulty Crankshaft Position Sensor (POS)
- Faulty starter motor
- Faulty select solenoid
One example of this would be when an bmw automatic car in placed in gear. To prevent the added drag from the torque converter and transmission from reducing the idling speed, the PCM will command the idle control valve to allow more air to enter the engine, while at the same time, adjusting the injector pulse width to inject more fuel to suit the increased amount of air. Note that the idle air control valve is closed by the PCM when the throttle plate is opened to prevent excess air from entering the engine.
