B3311 BMW Fault Code
Check B3311 OBD Fault Code ReasonLow Speed Fuel Pump Primary Circuit Malfunction The PCM monitors the low speed fuel pump (LFP) primary circuit output from the PCM.
The test fails if: When the LFP circuit is commanded on (grounded), excessive current draw is detected on the BMW LFP circuit; or when the LFP circuit is commanded off, voltage is not detected on the LFP circuit (the PCM expects to detect VPWR voltage coming through the low speed fuel pump relay coil to the LFP circuit). Open or shorted low fuel pump (LFP) circuit Open VPWR to low speed fuel pump relay Damaged low speed fuel pump relay Damaged PCM An open circuit or short to ground can only be detected with the low speed fuel pump.
B3311 Code Symptoms :
There are currently two main types of cylinder deactivation used today, depending on the type of engine. B3311 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 B3311
B3311 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 B3311 code ?
- Camshaft Position Sensor harness is open or shorted
- Faulty spark plug (s)
- Faulty Air fuel ratio (A/F) Sensor 1 Bank 1
- Improper ignition timing
Some systems require that the actuator has an adequate supply of brake fluid. Low brake fluid levels can mimic the symptoms of code B3311, so consult the manual to locate the brake fluid reservoir.
Bear in mind that a low fluid level can set code B3311 on some applications, so make sure that on fluid operated systems the fluid level is up to the mark before starting an electrical diagnosis.
