EDI DIAGNOSIS SERVICE MANUAL NUMBER 22
Page 5E-30 90-860074--1 FEBRUARY 2002
IAT (Intake Air Temperature) Sensor
Scan Code: P1110
Blink Code: 1112
Malfunction Indicator Lamp: ON
b
e
c
d
41
55
40
WHT/YEL
BLU/WHT
64
41
324
6440 55
1
75340
GRN/BLK
GRN
a
f
a-IAT / MAP Sensor Assembly
b-IAT Signal
c-5 Volt Reference Signal
d-MAP Signal
e-Sensor Ground
f-To Throttle Position Sensor
CIRCUIT DESCRIPTION:
The IAT sensor and MAP (Manifold Absolute Pressure) sensor form an assembly. The IAT
portion of the assembly is a thermistor (a resistor which changes value based on
temperature). Low temperature produces a high resistance, while high temperature causes
a low resistance.
The ECM supplies a 5 volt signal to the sensor through a resistor in the ECM and measures
the voltage. The ECM voltage will be high when the intake air is cold, and low when the
intake manifold air is hot.
A failure in the IAT sensor circuit should set a Scan Code P1110.
CKT PIN
NAME
55 Sensor Ground
64 IAT Signal