B3911 BMW Fault Code

Description:

BMW HO2S Sensor Circuit Malfunction (HO2S-11) During testing the HO2S Heaters are checked for opens/shorts and excessive current draw.
The BMW test fails when current draw exceeds a calibrated limit and/or an open or short is detected. Short to VPWR in harness or HO2S. Water in harness connector. Open VPWR circuit. Open GND circuit. Low battery voltage. Corrosion or poor mating terminals and wiring Damaged HO2S heater. Damaged PCM.

B3911 Code Symptoms :

There are currently two main types of cylinder deactivation used today, depending on the type of engine. B3911 code for the pushrod design which uses solenoids to alter the oil pressure delivered to the lifters. In their collapsed state, the lifters are unable to elevate their companion pushrods under the valve rocker arms, resulting in valves that cannot be actuated and remain closed.

Diagnosis And Repairing B3911

B3911 OBD 2 code on vehicles with electronically controlled automatic transmissions, the 3-4 shift solenoid is responsible for actuating the hydraulic circuits to activate clutches or bands that change gears inside the automatic transmission.

How to fix B3911 code ?

• Damaged camshaft position (CMP) sensor
• Failures of clutch motion/travel sensors.
• Faulty ignition coil (s)
• Open VPWR circuit

Some systems require that the actuator has an adequate supply of brake fluid. Low brake fluid levels can mimic the symptoms of code B3911, so consult the manual to locate the brake fluid reservoir.

Bear in mind that a low fluid level can set code B3911 on some applications, so make sure that on fluid operated systems the fluid level is up to the mark before starting an electrical diagnosis.