DTC P0073:00 [SKYACTIV-D 2.2]

id0102s4146000

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 4.9 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.
•  DTC is not stored in the PCM memory.
FAIL-SAFE FUNCTION
Not applicable
POSSIBLE CAUSE
•  Ambient temperature sensor connector or terminals malfunction
•  Ambient temperature sensor malfunction
•  PCM connector or terminals malfunction
•  Short to power supply in wiring harness between ambient temperature sensor terminal A and PCM terminal 2AX
•  Open circuit in wiring harness between the following terminals:
―  Ambient temperature sensor terminal A—PCM terminal 2AX
―  Ambient temperature sensor terminal B—PCM terminal 2AY
•  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
INSPECT AMBIENT TEMPERATURE SENSOR CONNECTOR CONDITION
•  Switch the ignition 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 7.
No
Go to the next step.
3
INSPECT AMBIENT TEMPERATURE SENSOR
•  Inspect the ambient temperature sensor.
•  Is there any malfunction?
Yes
Replace the ambient temperature sensor, then go to Step 7.
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].)
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
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 7.
No
Go to the next step.
5
INSPECT AMBIENT TEMPERATURE SENSOR SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
•  Verify that the ambient temperature sensor and PCM connectors are disconnected.
•  Switch the ignition ON (engine off).
•  Measure the voltage at the ambient temperature sensor terminal A (wiring harness-side).
•  Is the voltage 0 V?
Yes
Go to the next step.
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 2AX.
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 7.
6
INSPECT AMBIENT TEMPERATURE SENSOR CIRCUIT FOR OPEN CIRCUIT
•  Verify that the ambient temperature sensor and PCM connectors are disconnected.
•  Switch the ignition off.
•  Inspect for continuity between the following terminals (wiring harness-side):
―  Ambient temperature sensor terminal A—PCM terminal 2AX
―  Ambient temperature sensor terminal B—PCM terminal 2AY
•  Is there continuity?
Yes
Go to the next step.
No
Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
•  Ambient temperature sensor terminal A—PCM terminal 2AX
•  Ambient temperature sensor terminal B—PCM terminal 2AY
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.
7
VERIFY DTC TROUBLESHOOTING COMPLETED
•  Always reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  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.
8
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [SKYACTIV-D 2.2].)
No
DTC troubleshooting completed.