P646B Mazda Scrum OBD Code

OBD/2 P646B error code description and symptoms.

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.

As long as the throttle plate remains closed, the idling speed and quality is controlled by the PCM via the idle control valve, and as can be seen from the above it should be clear that idle control on a gasoline engine is a complex affair. For instance, if the engine is started in sub-zero temperatures, the PCM will command the idling control valve to allow less air to enter the engine to enrich the air/fuel mixture to create a condition which is roughly analogous to how chokes worked on carburetted engines to control idling in cold weather.

P646B Mazda Scrum Error Code Repair Process :

If your check engine light is illuminated, it's best to take it in for diagnostic testing, which can feel like a hassle. Because while the lights vary in appearance from vehicle to vehicle, all have the same basic meaning: There's a problem with the car's emissions system. The on-board diagnostics system P646B and engine control unit are in charge of monitoring a bunch of different , and if they get a reading that's a little out of whack, up pops the check engine light.

Common Causes of Mazda Scrum P646B OBD2 Code

A common cause of code P646B is the failure of , but there are several other possible causes as well, such as ;

Air fuel ratio (A/F) Sensor 1 Bank 1 harness is open or shorted
Exhaust gas leaks
Intake Valve Timing Control Solenoid Valve circuit poor electrical connection
Incorrect fuel pressure

P646B is a kind of Powertrain Trouble Code

Powertrain of a modern automobile, comprising engine (with exhaust system), transmission, drive shaft, suspension and the wheels. In a motor vehicle, the term powertrain or powerplant describes the main components that generate power and deliver it to the road surface, water, or air.

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

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P646B Mazda Scrum OBD Code

P646B Mazda Scrum Error Code Repair Process :

Common Causes of Mazda Scrum P646B OBD2 Code

P646B code for other Mazda cars