Neon L4-2.0L SOHC (1995)
Intake Air Temperature Sensor: Description and Operation
Intake Air Temp Sensor Voltage High
NAME OF CODE:
Intake Air Temp Sensor Voltage High
WHEN MONITORED:
With the ignition ON and the engine running.
SET CONDITION:
The intake air sensor circuit voltage at Powertrain Control Module (PCM) cavity 6 goes above 4.9 volts.
THEORY OF OPERATION:
The Intake Air Temperature sensor (IAT) is located in the intake manifold where it measures the temperature of the air that is about to enter the
combustion chambers. The IAT is a negative temperature coefficient (NTC) thermistor-type sensor (resistance varies inversely with temperature).
This means at cold temperatures its resistance is high so the voltage signal will be high. At high temperatures, resistance decreases and the voltage
will decrease. This allows the sensor to provide an analog voltage signal to PCM cavity 6. The PCM uses this signal to compensate for changes in
air density due to temperature.
POSSIBLE CAUSES:
-
Sensor signal circuit open
-
Sensor internally open
-
Sensor ground circuit open
-
Powertrain control module failure
-
Connector wires/terminals
