LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mazda >> 2017 >> CX-5 Grand Select, AWD >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (1 Of 5) >> DTC P0072-00: Ambient Temperature Sensor Circuit Low Input >> Diagnostic Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Procedure

DIAGNOSTIC PROCEDURE DESCRIPTION

STEP INSPECTION RESULTS ACTION
1 RECORD VEHICLE STATUS AT TIME OF DTC DETECTION TO UTILIZE WITH REPEATABILITY VERIFICATION
NOTE:
  • Recording can be facilitated using the screen capture function of the PC.
  • Record the snapshot data on the repair order.
- Go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY
  • Verify related Service Bulletins and/or on-line repair information availability.
  • Is any related repair information available?
Yes Perform repair or diagnosis according to the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 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 9.
No Go to the next step.
4 DETERMINE IF AMBIENT TEMPERATURE SENSOR OR WIRING HARNESS MALFUNCTION
  • Verify that the ambient temperature sensor connector is disconnected.
  • Switch the ignition ON (engine off).
    NOTE:
    • Another DTC may be stored by the PCM detecting an open circuit.
  • Measure the voltage at the ambient temperature sensor terminal A (wiring harness-side).
  • Is the voltage approx. 5 V?
Yes Replace the ambient temperature sensor, then go to Step 9.
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .)
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .)
No Go to the next step.
5 INSPECT AMBIENT TEMPERATURE SENSOR SIGNAL CIRCUIT FOR SHORT TO GROUND
  • Verify that the ambient temperature sensor connector is disconnected.
  • Switch the ignition off.
  • Inspect for continuity between ambient temperature sensor terminal A (wiring harness-side) and body ground.
  • Is there continuity?
Yes Disconnect the PCM connector and inspect the wiring harness for short to ground.
  • If the short to ground circuit could be detected in the wiring harness:
    • 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 ground.
    • Repair or replace the malfunctioning part.

    If there is no common connector:


Go to Step 9.
No Go to the next step.
6 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.
7 INSPECT AMBIENT TEMPERATURE SENSOR SIGNAL CIRCUIT AND GROUND CIRCUIT FOR SHORT TO EACH OTHER
  • Verify that the ambient temperature sensor and PCM connectors are disconnected.
  • Inspect for continuity between ambient temperature sensor terminals A and B (wiring harness-side).
  • Is there continuity?
Yes 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 2I
  • Ambient temperature sensor terminal B-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 a short to each other.
  • Repair or replace the malfunctioning part.

If there is no common connector:
  • Repair or replace the wiring harness which has a short to each other.

Go to Step 9.
No Go to the next step.
8 INSPECT AMBIENT TEMPERATURE SENSOR Yes Replace the ambient temperature sensor, then go to the next step.
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER] .)
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER] .)
No Go to the next step.
9 VERIFY DTC TROUBLESHOOTING COMPLETED Yes Repeat the inspection from Step 1.
Go to the next step.
No Go to the next step.
10 VERIFY AFTER REPAIR PROCEDURE Yes Go to the applicable DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .)
No DTC troubleshooting completed.