B278A Subaru G3x OBD Code

OBD/2 B278A error code description and symptoms.

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 PCM or TCM will set code B278A

One example of this would be when an automatic vehicle 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.

B278A Subaru G3x Error Code Repair Process :

For engine overboost condition check engine light is perhaps the most troubling of lights because it could mean so many different things, from you didn't screw the gas cap on tightly enough to look out for pistons flying through the hood and into the stratosphere. The easiest way to find out what this light is telling you is to hook your vehicle up to a scan tool. B278A error code diagnostic tool looks a little like an oversized calculator and plugs into a communication port inside the car. After you instruct it to perform the scan, it speaks engine overboost condition with your car's computers to find out exactly what's prompting the light to turn on.

Common Causes of Subaru G3x B278A OBD2 Code

A common cause of code B278A is the failure of Engine Overboost Condition, but there are several other possible causes as well, such as ;

Continuous oil flow to the VCT piston chamber
Faulty spark plug (s)
Faulty starter motor
Clogged or faulty fuel injector (s)

B278A is a kind of Body Trouble Code

Auto body problems aren't always easy to spot. Diagnosing auto body problems sometimes requires a little know-how. In this section you'll find articles dedicated to teaching you how to diagnose auto body problems.

Engine OBD 2 Codes website is a freeware resource center for engine trouble codes.

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B278A Subaru G3x OBD Code

B278A Subaru G3x Error Code Repair Process :

Common Causes of Subaru G3x B278A OBD2 Code

B278A code for other Subaru cars