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Home >> Mazda >> 2021 >> CX-9 Signature >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control System (3 Of 6) >> DTC P0340-00: Intake CMP Sensor Circuit Problem >> Diagnostic Procedure
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Diagnostic Procedure

DTC P0340:00 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 VERIFY RELATED PENDING CODE AND/OR DTC
Yes Go to the applicable PENDING CODE or DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.5T)] .)
No Go to the next step.
4 INSPECT INTAKE CMP SENSOR CONNECTOR CONDITION
  • Switch the ignition off.
  • Disconnect the intake CMP 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 14.
No Go to the next step.
5 INSPECT INTAKE CMP SENSOR POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT
  • Verify that the intake CMP 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 intake CMP sensor terminal C (wiring harness-side).
  • Is the voltage B+?
Yes Go to the next step.
No Inspect the ENGINE 1 15 A fuse.
  • If the fuse is blown:
    • Refer to appropriate wiring diagram and verify whether or not there is a common connector between ENGINE 1 15 A fuse and intake CMP sensor terminal C.

    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.
  • Replace the fuse.
  • If the fuse is damaged:
    • Replace the fuse.
  • If the fuse is normal:
    • Refer to appropriate wiring diagram and verify whether or not there is a common connector between main relay terminal C and intake CMP sensor terminal C.

    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 14.
6 INSPECT INTAKE CMP SENSOR SIGNAL CIRCUIT FOR SHORT TO GROUND
  • Verify that the intake CMP sensor connector is disconnected.
  • Switch the ignition off.
  • Inspect for continuity between intake CMP 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 appropriate wiring diagram and verify whether or not there is a common connector between intake CMP sensor terminal A and PCM terminal 1V.

    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.
  • If the short to ground circuit could not be detected in the wiring harness:

Go to Step 14.
No Go to the next step.
7 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 14.
No Go to the next step.
8 INSPECT INTAKE CMP SENSOR SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
  • Verify that the intake CMP sensor and PCM connectors are 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 intake CMP sensor terminal A (wiring harness-side).
  • Is the voltage 0 V?
Yes Go to the next step.
No Refer to appropriate wiring diagram and verify whether or not there is a common connector between intake CMP sensor terminal A and PCM terminal 1V.
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 14.
9 INSPECT INTAKE CMP SENSOR SIGNAL CIRCUIT AND GROUND CIRCUIT FOR SHORT TO EACH OTHER
  • Verify that the intake CMP sensor and PCM connectors are disconnected.
  • Switch the ignition off.
  • Inspect for continuity between intake CMP sensor terminals A and B (wiring harness-side).
  • Is there continuity?
Yes Refer to appropriate wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Intake CMP sensor terminal A-PCM terminal 1V
  • Intake CMP sensor terminal B-PCM terminal 1S

    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 14.
No Go to the next step.
10 INSPECT INTAKE CMP SENSOR CIRCUIT FOR OPEN CIRCUIT
  • Verify that the intake CMP sensor and PCM connectors are disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side):
    • Intake CMP sensor terminal A-PCM terminal 1V
    • Intake CMP sensor terminal B-PCM terminal 1S
  • Is there continuity?
Yes Go to the next step.
No Refer to appropriate wiring diagram and verify whether or not there is a common connector between the following terminals:
  • Intake CMP sensor terminal A-PCM terminal 1V
  • Intake CMP sensor terminal B-PCM terminal 1S

    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 14.
11 INSPECT INTAKE CMP SENSOR
Yes Replace the intake CMP sensor, then go to Step 14.
(See CAMSHAFT POSITION (CMP) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
No Go to the next step.
12 INSPECT CKP SENSOR CONNECTOR CONDITION
  • Switch the ignition off.
  • Disconnect the CKP 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 14.
No Go to the next step.
13 VERIFY ASSEMBLY CONDITION OF TIMING CHAIN
Yes Repair or replace the malfunctioning part. Assemble the timing chain using the correct timing, then go to the next step.
(See TIMING CHAIN REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .)
No Go to the next step.
14 VERIFY DTC TROUBLESHOOTING COMPLETED
Yes Repeat the inspection from Step 1.

Go to the next step.
No Go to the next step.
15 VERIFY AFTER REPAIR PROCEDURE
Yes Go to the applicable DTC inspection.
(See DTC TABLE [PCM (SKYACTIV-G 2.5T)] .)
No DTC troubleshooting completed.