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P1A05 BMW Fault Code

Check P1A05 OBD Fault Code Reason
Description:

The Camshaft Position sensor will signal the Engine Control Module when the #1 cylinder is ready for the spark plug to fire (top-dead-center on compression stroke).

The ECM uses the information from this sensor to help calculate fuel delivery and spark timing.

P1A05 Code Symptoms :

See P1A05 in engine

OBD P1A05 code and tailpipe testing are two different approaches to identify vehicles in need of repair. The OBD system looks for broken or malfunctioning emissions control components and P1A05, while tailpipe tests sample a vehicle's exhaust to see if it is above or below certain prescribed limits. Given the robust nature of today's emissions control components, it is entirely possible for an individual component to malfunction without leading to an immediate increase in emissions at the tailpipe.

In such cases, other components (like the catalyst) can temporarily compensate for the part that is broken however, these other components can only do double duty for so long before they, too, begin to malfunction. In addition, OBD also monitors for and other malfunctions in the fuel system problems that traditional tailpipe tests were not designed to identify. Most state and local areas also include a gas cap pressure test as part of an emission inspection.

Diagnosis And Repairing P1A05

P1A05 OBD2 reports a sensor fault, replacement of the sensor is unlikely to resolve the underlying problem. The fault is most likely to be caused by the systems that the sensor is monitoring, but might even be caused by the wiring to the sensor itself.

How to fix P1A05 code ?

See P1A05 repair manual
  • Exhaust gas leaks
  • Air fuel ratio (A/F) Sensor 1 Bank 1 harness is open or shorted
  • Improper ignition timing
  • Air fuel ratio (A/F) Sensor 1 Bank 1 harness is open or shorted

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.

BMW Cars that meet P1A05 error