What are the possible causes of the BMW P12A5 code?
- Faulty Manifold Absolute Pressure (MAP) sensor
- Open or short circuit in the Manifold Absolute Pressure sensor wiring harness
- Poor electrical connection in the Manifold Absolute Pressure sensor circuit
How to fix the BMW P12A5 code?
Start by checking the “Possible Causes” listed above. Visually inspect the wiring harness and associated connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
What are the possible symptoms of the BMW P12A5 code?
- Check Engine Light on (or Service Engine Soon warning light)
What does the BMW P12A5 code mean?
The Manifold Absolute Pressure (MAP) sensor is used to monitor engine load by sampling the vacuum in the intake manifold. At idle, a high vacuum will exist because the throttle valve is in the idle load position and the engine cylinders act as an air pump against a restriction. A higher vacuum exists during deceleration conditions because the throttle is in the idle load position and the engine speed is high. The intake manifold vacuum disappears when the throttle valve is open and the intake manifold pressure is approximately equal to atmospheric pressure. A higher vacuum exists during deceleration conditions because the throttle is in the idle load position and the engine speed is high.
The MAP sensor signal can be used to calculate the amount of fuel injection, ignition advance or retard rate, boost pressure control, and idle speed control.
The Digital Motor Electronics (DME) diagnostic determines whether the absolute pressure, intake manifold pressure, and charge pressure sensors all record a single pressure reading. The Diagnostic Trouble Code (DTC) is recognized when the value measured by the intake manifold pressure sensor is too high compared to the modeled value.