Hummer H1 Service Manual page 1092

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DTC P0113 Intake Air Temperature (IAT)
Sensor Circuit High Voltage
REFERNCE
CKP
SENSOR
SIGNAL
A
C5-B9
C29-A5
CKP
SENSOR
SIGNAL
Circuit Description
The intake air temperature sensor is a thermistor that controls
signal voltage to the PCM. When the air is cold, the sensor re-
sistance is high, therefore the PCM will see a high signal volt-
age. As air warms, sensor resistance becomes less and voltage
drops. This is a type B DTC.
Conditions for Setting the DTC
• Engine operating for 8 minutes.
• IAT less than or equal to -30°C (-22°F).
• Conditions met for 2 seconds.
Action Taken When the DTC Sets
Possible poor performance during cold weather operation.
Conditions for Clearing the MIL/DTC
• The PCM will turn the MIL off after three consecutive
trips without a fault condition.
• A History DTC will clear when forty consecutive
warm-up cycles that the diagnostic does not fail (Cool-
ant temperature has risen 5°C(40°F) from start up cool-
ant temperature and engine coolant temperature exceeds
160°F (71°C) that same ignition cycle).
• Use of a scan tool.
05745159
C
CRANK
5 VOLT
SHAFT
POSITION
SENSOR
(CKP)
SENSOR
GROUND
B
B
C5-B5 C5-B12
C27-C1 C27-D13 C27-C14
SENSOR 5 VOLT BOOST
GROUND REFERENCE SENSOR
SIGNAL
C
BOOST/
A
BARO
PRESSURE
SENSOR
A
B
C5-B10
359 BK
C5-C5
C5-B11
TO
TFT
SENSOR
C29-B12
SENSOR IAT
GROUND SENSOR
SIGNAL
Diagnostic Aids
The scan tool displays intake air temperature in degrees centi-
grade. Refer to "Intermittent" on page 13. A "skewed" sensor
could result in poor driveability complaints.
Test Description
Number(s) below refer to the step number(s) on the diagnostic
Table.
5. This step determines if P0113 is a hard failure or an intermit-
tent condition.
6. This step will determine if there is a wiring problem or
a faulty PCM.
PCM/Tech 1 Scan Tool 27
INTAKE AIR
TEMPERATURE
SENSOR (IAT)
A
ENGINE
COOLANT
TEMP
SENSOR
(ECT)
B
C5-C4
ECT
POWERTRAIN
SENSOR
CONTROL
SIGNAL
MODULE
9-S12-066