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Manifold Absolute Pressure Sensor(MAP) Circuit Malfuntion
DTC
P0105
Manifold Absolute Pressure Sensor(MAP) Circuit Malfuntion
P0107
Manifold Absolute Pressure Sensor(MAP) Circuit Low Voltage
P0108
Manifold Absolute Pressure Sensor (MAP) Circuit High Voltage
DESCRIPTION
The MAP sensor is essentially a strain gauge used to measure the pressure in the surge tank. Inside the
sensor is a metal diaphragm with a small wire attached. The diaphragm flexes according to changes in
pressure. When the diaphragm flexes, the wire attached to it stretches, changing the resistance of the
wire. ECU applies five volts to the MAP sensor and measures the voltage drop across the sensor. The
sensor output is in volts and as pressure decreases, the voltage drop across the sensor increases. Since
the MAP sensor is used as an air flow sensor, the sensor signal is an important input. The ECU uses the
information to determine fuel amount and ignition timing.
TROUBLESHOOTING GUIDE
Background
a. The MAP sensor outputs a voltage which corresponds to the
pressure of surge tank.
b. ECU checks whether this voltage is within a specified range.
Check Area
a. Ignition switch : ON
b. Sixty seconds or more have passed since the staring sequence
was completed.
c. Battery voltage is 8V or more.
Judgment Criteria
a. Sensor output voltage has continued to be 4.22V or higher
[corresponding to a surge tank pressure of 107kPa(15.5psi) or
higher] for 4 sec.
b. Sensor output voltage has continued to be 0.79V or lower
[corresponding to a surge tank pressure of 20 kPa(2.9 psi) or
lower] for 4 sec.
CIRCUIT DIAGRAM
DTC detection condition
Diagnostic item
a. MAP sensor failed
b. Open or shorted MAP sensor
circuit, or loose connector
c. ECU failed
Probable cause
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