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P1A84 BMW Fault Code

Check P1A84 OBD Fault Code Reason
Description:

Variable Cam Timing Over-advanced (Bank 1) The comprehensive component monitor (CCM) monitors the VCT position for an over-advanced camshaft timing.
The test fails when the camshaft timing exceeds a maximum calibrated value or remains in an advanced position.

BMW cam timing improperly set No oil flow to the VCT piston chamber Low oil pressure VCT solenoid valve stuck closed Camshaft advance mechanism binding (VCT unit) P1A84 DTC is a check of the VCT unit.

P1A84 Code Symptoms :

See P1A84 in engine

The P1A84 Check Engine lamp 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. P1A84 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 with your car's computers to find out exactly what's prompting the light to turn on.

Diagnosis And Repairing P1A84

Parts or components should not be replaced with reference to only a P1A84 DTC. The vehicle service manual should be consulted for more information on possible causes of the fault, along with required testing.

How to fix P1A84 code ?

  • Erratic camshaft position due to low oil pressure
  • 1Camshaft Position Sensor circuit poor electrical connection
  • Ignition coils harness is open or shorted
  • Faulty select solenoid

A good starting point in your diagnosis is checking all system fuses and fusible links. This can be done using the BMW DVOM on the voltage setting. You will want to test the fuses with circuits loaded.

Some fuses will appear normal until a load is placed on their respective circuit; at which point they will fail. This has been the cause of many 'phantom malfunctions'. Consult your vehicle information source for fuse and fusible link locations. If all fuses are in working order, you may want to check TCM relay operation by swapping identical relays. Usually the horn relay, starter relay, fuel pump relay, air conditioning clutch relay, and controller relays are similar enough in design to swap for diagnostic purposes.

BMW Cars that meet P1A84 error