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Home >> Mazda >> 2017 >> 5 GT, Standard Trans >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic - Engine Control (1 Of 3) >> DTC P0340-00: CMP Sensor Circuit Problem >> Diagnostic Procedure
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Diagnostic Procedure

DTC P0340:00 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA HAS BEEN RECORDED
  • Has the FREEZE FRAME DATA (Mode 2)/snapshot data been recorded?
Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 2)/snapshot data on the repair order, then 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 CMP SENSOR CONNECTOR CONDITION
  • Switch the ignition to off.
  • 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 13.
No Go to the next step.
4 INSPECT CMP SENSOR GROUND CIRCUIT FOR OPEN CIRCUIT
  • Verify that the CMP sensor connector is disconnected.
  • Inspect for continuity between CMP sensor terminal A (wiring harness-side) and body ground.
  • Is there continuity?
Yes Go to the next step.
No Repair or replace the wiring harness for a possible open circuit, then go to Step 13.
5 INSPECT CMP SENSOR CIRCUIT FOR SHORT TO GROUND
  • Verify that the CMP sensor connector is disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground:
    • CMP sensor terminal C
    • CMP sensor terminal B
  • Is there continuity?
Yes If the short to ground circuit could be detected:
  • Repair or replace the wiring harness for a possible short to ground.

    If the short to ground circuit could not be detected:

  • Replace the PCM (short to ground in the PCM internal circuit). (See PCM REMOVAL/INSTALLATION .)

Go to Step 13.
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 13.
No Go to the next step.
7 INSPECT CMP SENSOR SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
  • Verify that the CMP sensor and PCM connectors are disconnected.
  • Switch the ignition to ON (engine off).
  • Measure the voltage at the CMP sensor terminal B (wiring harness-side).
  • Is there any voltage?
Yes Repair or replace the wiring harness for a possible short to power supply, then go to Step 13.
No Go to the next step.
8 INSPECT CMP SENSOR POWER SUPPLY CIRCUIT AND SIGNAL CIRCUIT FOR SHORT TO EACH OTHER
  • Verify that the CMP sensor and PCM connectors are disconnected.
  • Switch the ignition to off.
  • Inspect for continuity between CMP sensor terminals C and B (wiring harness-side).
  • Is there continuity?
Yes Repair or replace the wiring harness for a possible short to each other, then go to Step 13.
No Go to the next step.
9 INSPECT CMP SENSOR CIRCUIT FOR OPEN CIRCUIT
  • Verify that the CMP sensor and PCM connectors are disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side):
    • CMP sensor terminal C-PCM terminal 2AM
    • CMP sensor terminal B- PCM terminal 2S
  • Is there continuity?
Yes Go to the next step.
No Repair or replace the wiring harness for a possible open circuit, then go to Step 13.
10 INSPECT CMP SENSOR
Yes Replace the CMP sensor, then go to Step 13.
(See CAMSHAFT POSITION (CMP) SENSOR REMOVAL/INSTALLATION .)
No Go to the next step.
11 INSPECT CKP SENSOR CONNECTOR CONDITION
  • Switch the ignition to 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 13.
No Go to the next step.
12 VERIFY VALVE TIMING MECHANISM INSTALLATION
  • Verify the valve timing mechanism installation for the following parts:
    • Timing chain
    • Loose camshaft sprocket lock bolt
    • Loose crankshaft pulley lock bolt
  • Is the valve timing mechanism installed correctly?
Yes Go to the next step.
No Reinstall the following parts correctly, then go to the next step.
  • Timing chain
  • Camshaft sprocket
  • Crankshaft pulley
13 VERIFY DTC TROUBLESHOOTING COMPLETED
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE .)
  • Start the engine.
  • Access the MAF PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST .)
    NOTE:
    • The MAF PID should indicate 1.95 g/s {0.25 lb/min.} or above during this test.
  • Perform the DTC Reading Procedure. (See ON-BOARD DIAGNOSTIC TEST .)
  • Is the same DTC present?
Yes Repeat the inspection from Step 1.

Go to the next step.
No Go to the next step.
14 VERIFY AFTER REPAIR PROCEDURE
Yes Go to the applicable DTC inspection.
(See DTC TABLE .)
No DTC troubleshooting completed.