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Home >> Mazda >> 2007 >> 6 Mazdaspeed >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System L3 With TC] >> DTC P0340 >> Diagnostic procedure
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Diagnostic procedure

DTC P0340 DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA HAS BEEN RECORDED 
  • Has the FREEZE FRAME DATA been recorded?
Yes Go to the next step.
No Record FREEZE FRAME DATA on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Check for related Service Bulletins and/or online repair information availability.
  • Is any related repair information available?
Yes Perform the 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 CMP SENSOR VOLTAGE 
  • Disconnect the CMP sensor connector.
  • Connect a voltmeter between CMP sensor connector terminals A and C (sensor-side).
  • Inspect the voltage in AC range while cranking the engine.
  • Is there any voltage?
Yes Go to the next step.
No Go to step 10.
4 INSPECT CMP SENSOR CONNECTOR FOR POOR CONNECTION 
  • Verify that the CMP sensor connector is connected securely.
  • Is the connector normal?
Yes Go to the next step.
No Reconnect the connector, then, go to Step 15.
5 INSPECT CMP CIRCUIT FOR SHORT TO POWER 
  • Turn ignition switch OFF.
  • Disconnect the CMP sensor connector.
  • Turn ignition switch to the ON position (Engine off)
  • Measure voltage between the following terminals:
    • CMP sensor connector terminal C (harness-side) and body ground
    • CMP sensor connector terminal B (harness-side) and body ground
  • Is the voltage B+  ?
Yes Repair or replace the suspected wiring harness, then go to Step 15.
No Go to the next step.
6 INSPECT CMP CIRCUIT FOR SHORT TO GROUND 
  • inspect for continuity between the following terminal and body ground:
    • CMP sensor connector terminal A (harness-side)
    • CMP sensor connector terminal C (harness-side)
  • Is there continuity?
Yes Repair or replace the suspected wiring harness, then go to Step 15.
No Go to the next step.
7 INSPECT CMP CIRCUITS FOR SHORT CIRCUIT 
  • Inspect for continuity between CMP sensor connector terminals A and C (harness-side).
  • Is there continuity?
Yes Repair or replace the suspected wiring harness, then go to Step 15.
No Go to the next step.
8 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Disconnect the PCM connector.
  • Inspect for poor connection (damaged, pulled-out terminals, corrosion, etc)..
  • Is there any malfunction?
Yes Repair the terminal, then go to Step 15.
No Go to the next step.
9 INSPECT CMP CIRCUIT FOR OPEN CIRCUIT 
  • Inspect for continuity between the following circuits:
    • CMP sensor terminal A (harness-side) and main relay
    • CMP sensor terminal B (harness-side) and PCM terminal 2H (harness-side)
    • CMP sensor terminal C (harness-side) and PCM terminal 2E (harness-side)
  • Is there continuity?
Yes Go to Step 11.
No Repair or replace the suspected wiring harness, then go to Step 15.
10 INSPECT CMP SENSOR 
Yes Go to the Step 15.
No Replace the CMP sensor and go to Step 15.
11 VERIFY CKP SENSOR INSTALLATION 
Yes Go to the next step.
No Reinstall the CKP sensor and go to Step 15.
12 VERIFY VALVE TIMING MECHANISM INSTALLATION 
  • Verify the valve timing mechanism installation for the following parts:
    • Timing chain misinstallation
    • 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 and go to Step 15.
  • Timing chain
  • Camshaft sprocket
  • Crankshaft pulley
13 INSPECT STOPPER PIN MECHANISM 
Yes Go to the next step.
No Replace the variable valve timing actuator, then go to Step 15.
14 INSPECT ROTOR POSITION 
Yes VARIABLE VALVE TIMING MECHANISM NORMAL 
NOTE:
  • This DTC is detected as an intermittent concern.
  • The intermittent concern might be removed by cleaning the variable valve timing mode control function.

Go to the next step.
No Replace the variable valve timing actuator, then go to the next step.
15 VERIFY TROUBLESHOOTING OF DTC P0340 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Turn ignition switch to the ON position (Engine off).
  • Clear the DTC from the PCM memory using the WDS or equivalent.
  • Start the engine.
  • Access the MAF PID using the WDS or equivalent.
    NOTE:
    • The MAF PID should indicate 1.95 g/s {0.25 lb/min.} or above  during this test
  • Is same DTC present?
Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION ).
No Go to the next step.
16 VERIFY AFTER REPAIR PROCEDURE 
Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No Troubleshooting completed.