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Home >> Mazda >> 2017 >> CX-9 Signature >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (1 Of 5) >> DTC P0237-00; Boost Pressure Sensor Circuit Low Input >> Diagnostic Procedure
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Diagnostic Procedure

DIAGNOSTIC PROCEDURE

STEP INSPECTION 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 FREEZE FRAME DATA/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 BOOST PRESSURE SENSOR/BOOST AIR TEMPERATURE SENSOR CONNECTOR CONDITION
  • Switch the ignition off.
  • Disconnect the boost pressure sensor/boost air 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 8.
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 8.
No Go to the next step.
5 INSPECT BOOST PRESSURE SENSOR CIRCUIT FOR SHORT TO GROUND
  • Verify that the boost pressure sensor/boost air temperature sensor and PCM connectors are disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground:
    • Boost pressure sensor/boost air temperature sensor terminal C
      • Boost pressure sensor/boost air temperature sensor terminal D
  • Is there continuity?
Yes Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Boost pressure sensor/boost air temperature sensor terminal C-PCM terminal 2AE
  • Boost pressure sensor/boost air temperature sensor terminal D-PCM terminal 2AS

    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:

  • Repair or replace the wiring harness which has a short to ground.

Go to Step 8.
No Go to the next step.
6 INSPECT BOOST PRESSURE SENSOR SIGNAL CIRCUIT AND GROUND CIRCUIT FOR SHORT TO EACH OTHER
  • Verify that the boost pressure sensor/boost air temperature sensor and PCM connectors are disconnected.
  • Inspect for continuity between boost pressure sensor/boost air temperature sensor terminals D and A (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:
  • Boost pressure sensor/boost air temperature sensor terminal D-PCM terminal 2AS
  • Boost pressure sensor/boost air temperature sensor terminal A-PCM terminal 2J

    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 8.
No Go to the next step.
7 INSPECT BOOST PRESSURE SENSOR Yes Replace the boost pressure sensor/boost air temperature sensor, then go to the next step.
(See BOOST PRESSURE SENSOR/BOOST AIR TEMPERATURE SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
No Go to the next step.
8 VERIFY DTC TROUBLESHOOTING COMPLETED Yes Repeat the inspection from Step 1.
Go to the next step.
No Go to the next step.
9 VERIFY AFTER REPAIR PROCEDURE Yes Go to the applicable DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.5T)] .)
No DTC troubleshooting completed.