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Home >> Mazda >> 2011 >> RX-8 R3, 1.3 4 >> Repair and Diagnosis >> Engine Performance >> System >> On-Board Diagnostic [Engine Control System] >> DTC P1681
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DTC P1681

DTC P1681 OCV circuit high input
DETECTION CONDITION 
  • The PCM monitors input voltage from the OCV. If the OCV current is more than 3.5 A  for 2 s  when the battery voltage is more than 10 V, the PCM determines the OCV circuit has a malfunction.

Diagnostic support note 
  • This is a continuous monitor (other).
  • The MIL does not illuminate.
  • FREEZE FRAME DATA (Mode 2/Mode 12) is not available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • OCV connector or terminals malfunction
  • PCM connector or terminals malfunction
  • Short to power supply in wiring harness between OCV terminal A and PCM terminal 2E
  • OCV malfunction
  • PCM malfunction
G07878137
DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 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.
2 INSPECT OCV CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the OCV connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 6.
No Go to the next step.
3 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 6.
No Go to the next step.
4 INSPECT OCV CONTROL CIRCUIT FOR SHORT TO POWER SUPPLY 
  • OCV and PCM connectors are disconnected.
  • Turn the ignition switch to the ON position (engine off).
  • Measure the voltage between OCV terminal A (wiring harness-side) and body ground.
  • Is the voltage B+  ?
 Yes Repair or replace the wiring harness for a possible short to power supply, then go to Step 6.
No Go to the next step.
5 INSPECT OCV 
 Yes Replace the OCV, then go to the next step.
(See OIL CONTROL VALVE (OCV) REMOVAL/INSTALLATION ).
No Go to the next step.
6 VERIFY TROUBLESHOOTING OF DTC P1681 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS.

    (See AFTER REPAIR PROCEDURE ).

  • Perform the KOER self test.

    (See KOEO/KOER SELF TEST ).

  • Is the same DTC present?
 Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION ).
No Go to the next step.
7 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.
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