DTC P0112, P0113, or P0114 - LLU
Diagnostic Instructions
DTC Descriptors
DTC P0112 00: Inlet Air Temperature (IAT) Sensor
Circuit Low Voltage
DTC P0113 00: Inlet Air Temperature (IAT) Sensor
Circuit High Voltage
DTC P0114 00: Inlet Air Temperature (IAT) Sensor
Circuit Intermittent
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
IAT Sensor Signal
|
P0112 00, P0114 00
|
P0113 00, P0114 00
|
P0113 00, P0114 00
|
P0114 00
|
Low Reference
|
-
|
P0113 00, P0114 00
|
P0113 00, P0114 00
|
P0114 00
|
Typical Scan Tool Data
IAT Sensor
Circuit
|
Short to Ground
|
Open
|
Short to Voltage
|
Operating Conditions: Engine operating
in closed loop.
Parameter Normal Range: Varies with
ambient temperature
|
IAT Sensor Signal
|
150°C (302°F)
|
-40°C (-40°F)*
|
-40°C (-40°F)*
|
Low Reference
|
-
|
-40°C (-40°F)*
|
-40°C (-40°F)*
|
* Internal ECM or sensor damage may occur if the circuit is
shorted to B+.
|
Circuit/System Description
The inlet air temperature (IAT) sensor is an integral part
of the mass air flow (MAF) sensor. The inlet air
temperature (IAT) sensor is a variable resistor that measures
the temperature of the air entering the engine. The IAT sensor has
a signal circuit and a low reference circuit. The engine control
module (ECM) supplies 5 V to the IAT signal circuit and
an ground for the IAT low reference circuit.
The following table illustrates the difference between
temperature, resistance, and voltage:
IAT
|
IAT Resistance
|
IAT Signal Voltage
|
Cold
|
High
|
High
|
Warm
|
Low
|
Low
|
Conditions for Running the DTC
P0112 00
• |
DTCs P0117 00, or P0118 00, are not
set. |
• |
The engine run time is greater than
10 s. |
• |
The engine coolant temperature (ECT) sensor is
less than 150°C (302°F). |
• |
The vehicle speed is greater than 0 km/h
(0 MPH). |
• |
The DTC runs continuously once the above
conditions are met. |
P0113 00
• |
DTCs P0107 00, P0108 00,
P0117 00, or P0118 00, are not set. |
• |
The engine run time is greater than
10 s. |
• |
The airflow into the engine is less than
512 g/s. |
• |
The engine coolant temperature (ECT) sensor is
greater than -40°C (-40°F). |
• |
The vehicle speed is less than 15.5 km/h
(9.6 MPH). |
• |
The DTC runs continuously once the above
conditions are met. |
P0114 00
• |
DTC P0112 00, or P0113 00 is not
set. |
• |
The ignition is ON or the engine is running. |
• |
The battery voltage is greater than 9 V. |
Conditions for Setting the DTC
P0112 00
The ECM detects that the IAT sensor is greater than 149°C
(300°F) for greater than 10 s.
P0113 00
The ECM detects that the IAT sensor parameter is colder than
-40°C (-40°F) for greater than 4 s.
P0114 00
The ECM detects that the IAT sensor signal has abruptly changed
a minimum of 10°C (18°F) warmer or colder for greater than
2 s.
Action Taken When the DTC Sets
DTCs P0112 00, P0113 00 and P0114 00 are Type B
DTCs.
Conditions for Clearing the DTC
DTCs P0112 00, P0113 00 and P0114 00 are Type B
DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- If the ignition has been OFF for 8 h or greater,
the B75B Mass Air Flow/Intake Air Temperature Sensor
(IAT 1), the B65 Intake Manifold Pressure and Air
Temperature Sensor (IAT 2) and the B34A Engine Coolant
Temperature Sensor 1 should be within 9°C (16°F) of each
other. Ignition ON, observe the scan tool IAT Sensor, IAT
Sensor 2 and the ECT Sensor parameters. Compare those sensor
parameters to each other to determine if the condition is
current.
- Engine running, observe the scan tool IAT Sensor
parameter. The reading should be between -39 to +120°C (-38 to
+248°F) depending on the current ambient temperature and the
vehicle operating conditions.
- Operate the vehicle within the conditions for running
the DTC to verify the DTC does not reset. You may also operate the
vehicle within the conditions that you observed from the freeze
frame/failure records data.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the
B75B Mass Air Flow/Intake Air Temperature Sensor.
- Ignition OFF for 90 s, test for less than
5 Ω between the ground circuit terminal 2 and
ground.
⇒ |
If greater than the specified range, test the
ground circuit for an open/high resistance. |
- Ignition ON, test for 4.8-5.2 V between the
B75B Mass Air Flow/Intake Air Temperature Sensor (IAT 1)
low reference circuit terminal 3 and ground.
⇒ |
If less than the specified range, test the low
reference circuit for an open/high resistance. If the circuit tests
normal, replace the K20 Engine Control Module. |
- Ignition ON, verify the scan tool IAT Sensor parameter
is colder than -39°C (-38°F).
⇒ |
If warmer than the specified range, test the
signal circuit terminal 1 for a short to ground. If the
circuit tests normal, replace the K20 Engine Control
Module. |
- Install a 3 A fused jumper wire between the
B75B Mass Air Flow/Intake Air Temperature Sensor signal
circuit terminal 3 and the low reference terminal 1.
Verify the scan tool IAT Sensor parameter is warmer than 142°C
(288°F).
⇒ |
If less than the specified range, test the signal
circuit for a short to voltage or an open/high resistance. If the
circuit tests normal replace the K20 Engine Control
Module. |
- If all circuits/connections test normal, replace the
B75B Mass Air Flow/ Inlet Air Temperature Sensor.
Component Testing
Static Test
Measure and record the resistance of the B75B Mass Air
Flow/Intake Air Temperature Sensor (IAT 1) at various
ambient temperatures, then compare those measurements to the
Temperature Versus Resistance table.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
|