C0649 BMW Fault Code

Description:

The Transmission Fluid Pressure Switch allows the engine's control module (PCM) or Transmission Control Module (TCM) to use hydraulic fluid to engage the clutches in the transmission to allow for smoother shifting while driving. If the PCM or TCM detects an issue with the hydraulic clutch or the pressure switch, the BMW PCM or TCM will set code C0649

C0649 Code Symptoms :

OBD C0649 code and tailpipe testing are two different approaches to identify vehicles in need of repair. The OBD system looks for broken or malfunctioning emissions control components and C0649, while tailpipe tests sample a vehicle's exhaust to see if it is above or below certain prescribed limits. Given the robust nature of today's emissions control components, it is entirely possible for an individual component to malfunction without leading to an immediate increase in emissions at the tailpipe.

In such cases, other components (like the catalyst) can temporarily compensate for the part that is broken however, these other components can only do double duty for so long before they, too, begin to malfunction. In addition, OBD also monitors for and other malfunctions in the fuel system problems that traditional tailpipe tests were not designed to identify. Most state and local areas also include a gas cap pressure test as part of an emission inspection.

Diagnosis And Repairing C0649

C0649 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 C0649 code ?

• Exhaust tube
• Faulty Camshaft Position Sensor
• Camshaft advance mechanism binding (VCT unit)
• Faulty ignition coil (s)

To check for an open circuit, trace along the length of the transmission control circuit, checking for breaks in the wiring. Repair any broken wiring and make sure all connectors are fully seated and locked.

Pay close attention to connectors, looking for corrosion, bent or broken pins, or moisture in the connector. Repair any connector issues even if they are not specifically part of the transmission control circuit as they may serve a function in providing power to the transmission control circuit.