DTC P0073:00 [SKYACTIV-G 2.0, SKYACTIV-G 2.5]

id0102h4146000

DTC P0073:00

Ambient temperature sensor circuit high input
DETECTION CONDITION
•  The PCM monitors the input signal from the ambient temperature sensor. If the voltage from the ambient temperature sensor is above 4.8 V for 5 s, the PCM determines that the ambient temperature sensor circuit has a malfunction.
Diagnostic support note
•  This is a continuous monitor (other).
•  The check engine light does not illuminate.
•  FREEZE FRAME DATA (Mode 2)/Snapshot data is not available.
•  The DTC is stored in the PCM memory.
FAIL-SAFE FUNCTION
Not applicable
POSSIBLE CAUSE
•  Ambient temperature sensor connector or terminals malfunction
•  PCM connector or terminals malfunction
•  Ambient temperature sensor malfunction
•  Short to power supply in wiring harness between ambient temperature sensor terminal A and PCM terminal 2I
•  Open circuit in wiring harness between the following terminals:
―  Ambient temperature sensor terminal A—PCM terminal 2I
―  Ambient temperature sensor terminal B—PCM terminal 2AJ
•  PCM malfunction

Diagnostic Procedure

STEP

INSPECTION

ACTION
1
VERIFY RELATED SERVICE INFORMATION AVAILABILITY
•  Verify related Service Information availability.
•  Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service Information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
2
CLASSIFY AMBIENT TEMPERATURE SENSOR MALFUNCTION OR WIRING HARNESS MALFUNCTION
•  Access the AAT PID using the M-MDS.
•  Verify the AAT PID value.
•  Is the AAT PID value 5 V or B+?
Yes
Go to Step 6.
No
Go to the next step.
3
INSPECT AMBIENT TEMPERATURE SENSOR CONNECTOR CONDITION
•  Switch the ignition to off.
•  Disconnect the ambient temperature sensor connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector and/or terminals, then go to Step 9.
No
Go to the next step.
4
INSPECT PCM CONNECTOR CONDITION
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector and/or terminals, then go to Step 9.
No
Go to the next step.
5
INSPECT AMBIENT TEMPERATURE SENSOR
•  Inspect the ambient temperature sensor.
•  Is there any malfunction?
Yes
Replace the ambient temperature sensor, then go to Step 9.
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].)
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
No
Go to Step 9.
6
CLASSIFY AMBIENT TEMPERATURE SENSOR SIGNAL CIRCUIT MALFUNCTION OR AMBIENT TEMPERATURE SENSOR GROUND CIRCUIT MALFUNCTION
•  Switch the ignition to off.
•  Disconnect the ambient temperature sensor connector.
•  Access the AAT PID using the M-MDS.
•  Verify the AAT PID value.
•  Is the AAT PID value 5 V or B+?
Yes
Go to the next step.
No
Go to Step 8.
7
INSPECT AMBIENT TEMPERATURE SENSOR SIGNAL CIRCUIT FOR OPEN CIRCUIT
•  Verify that the ambient temperature sensor connector is disconnected.
•  Switch the ignition to off.
•  Disconnect the PCM connector.
•  Inspect for continuity between ambient temperature sensor terminal A (wiring harness-side) and PCM terminal 2I (wiring harness-side).
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between ambient temperature sensor terminal A and PCM terminal 2I.
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has a short to power supply.
Go to Step 9.
No
Refer to the wiring diagram and verify whether or not there is a common connector between ambient temperature sensor terminal A and PCM terminal 2I.
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to Step 9.
8
INSPECT AMBIENT TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT
•  Verify that the ambient temperature sensor connector is disconnected.
•  Switch the ignition to off.
•  Disconnect the PCM connector.
•  Inspect for continuity between ambient temperature sensor terminal B (wiring harness-side) and PCM terminal 2AJ (wiring harness-side).
•  Is there continuity?
Yes
Replace the ambient temperature sensor, then go to the next step.
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].)
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
No
Refer to the wiring diagram and verify whether or not there is a common connector between ambient temperature sensor terminal B and PCM terminal 2AJ.
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to the next step.
9
VERIFY DTC TROUBLESHOOTING COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Start the engine and warm it up completely.
•  Perform the KOEO or KOER self test.
•  Is the same DTC present?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the PCM.
Go to the next step.
No
Go to the next step.
10
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
No
DTC troubleshooting completed.