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P042A BMW Fault Code

Check P042A OBD Fault Code Reason
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 P042A

P042A Code Symptoms :

See P042A in engine

The original multi-displacement system turned off opposite pairs of cylinders, allowing the engine to have three different configurations and displacements. P042A code had an elaborate diagnostics procedure, including showing engine trouble codes on the air conditionning display. However, the system was troublesome, misunderstood by customers, and a rash of unpredictable failures led to the technology being quickly retired.

Diagnosis And Repairing P042A

P042A 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 P042A code ?

See P042A repair manual
  • Exhaust tube
  • Failures of clutch motion/travel sensors.
  • Faulty variable valve timing (VVT)
  • 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 P042A, so consult the manual to locate the brake fluid reservoir.

Bear in mind that a low fluid level can set code P042A on some applications, so make sure that on fluid operated systems the fluid level is up to the mark before starting an electrical diagnosis.

BMW Cars that meet P042A error