C0304 BMW Fault Code

Description:

The Transmission Range Sensor (also referred to as the PRNDL input an/or neutral safety switch) tells the transmission control module (TCM) an the engine control module (PCM) that the transmission is in park, reverse, neutral, drive, low, 2nd, 3rd etc. It is attached directly to the manual valve of transmission, so when the shift lever is moved from park to drive, the Transmission Range Sensor communicates this critical information to the above mentioned vehicle control module systems.

C0304 Code Symptoms :

There are currently two main types of cylinder deactivation used today, depending on the type of engine. C0304 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 C0304

C0304 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 C0304 code ?

• Engine Control Module (ECM)
• Camshaft advance mechanism binding (VCT unit)
• Damaged ECM
• Variable Camshaft Timing (VCT) position circuit poor electrical connection

Some systems require that the actuator has an adequate supply of brake fluid. Low brake fluid levels can mimic the symptoms of code C0304, so consult the manual to locate the brake fluid reservoir.

Bear in mind that a low fluid level can set code C0304 on some applications, so make sure that on fluid operated systems the fluid level is up to the mark before starting an electrical diagnosis.