Manifold Absolute Pressure Sensor

FAULT ID
32

TITLE
Manifold Absolute Pressure Sensor

BACKGROUND
- The manifold absolute pressure sensor outputs a voltage which corresponds to the intake manifold plenum pressure.
- The engine control module checks whether this voltage is within a specified range.

RANGE OF CHECK (1)
- Ignition switch: ON

SET CONDITIONS (1)
- Sensor output voltage is 4.5 V or more (corresponding to an absolute pressure of 115 kPa (34.1 in.Hg) or more for 4 seconds.

RANGE OF CHECK (2)
- The throttle position sensor output voltage is 1.25 V or more.

or

- Vehicle is stationary.

SET CONDITIONS (2)
- Sensor output voltage is 0.2 V or less (corresponding to an absolute pressure of 4.93 kPa (1.46 in.Hg) or less) for 4 seconds.

EFFECT
Limp-in
- Uses the throttle position sensor signal and engine speed signal (crankshaft position sensor signal) to read the injector basic drive time and basic ignition timing from the preset map.
- Fixes the IAC motor in the appointed position so idle air control is not performed.

PROBABLE CAUSES
- Manifold absolute pressure sensor failed.
- Open or shorted manifold absolute pressure sensor circuit, or loose connector.
- Engine control module failed.