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B0638 BMW Fault Code

Check B0638 OBD Fault Code Reason
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.

B0638 Code Symptoms :

See B0638 in engine

If your vehicle failed a B0638 test and the B0638 Check Engine Light is NOT on, chances are you have a problem with the OBDII system, a burned out MIL lamp, or a faulty catalytic converter. The converter is essentially an afterburner that cleans up the exhaust after it exits the engine. The OBDII system uses B0638 a ownstream oxygen sensor to monitor the efficiency of the converter, and it should detect a drop in converter efficiency if the converter has been contaminated or is failing (ignition misfiring, leaky exhaust valves, and oil burning can all damage the converter). What you want to look : Any conditions that might cause ignition misfire, an overly rich or lean fuel condition, or loss of compression.

Diagnosis And Repairing B0638

B0638 the main thing to check is to verify the operation of the VCT solenoid. You're looking for a sticking or stuck VCt solenoid valve caused by contamination. Refer to vehicle specific repair manual to perform component tests for the VCT unit.

How to fix B0638 code ?

  • Engine Control Module (ECM)
  • Exhaust tube
  • Camshaft Position Sensor harness is open or shorted
  • Camshaft Position Sensor harness is open or shorted

Regardless of the design though, the purpose of all clutch actuating systems is to improve the driving experience by removing the need for manual clutch operation by the driver.

Computer-controlled clutch actuating systems work particularly well in dual clutch systems where one clutch controls gear changes of even-numbered gear ratios, and a second clutch that controls gear changes of odd-numbered ratios.

BMW Cars that meet B0638 error