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DTC P1680

DTC P1680 OCV circuit low input
DETECTION CONDITION 
  • The PCM monitors input voltage from the OCV. If the voltage of the OCV input terminal is less than the specification for 1 s  when the battery voltage is more than 10 V, the PCM determines the OCV circuit voltage is low.

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
  • Short to ground or open circuit in OCV power supply circuit
    • Short to ground in wiring harness between main relay terminal C and OCV terminal B
    • OCV related fuse malfunction
    • Open circuit in wiring harness between main relay terminal C and OCV terminal B
  • Short to ground in wiring harness between OCV terminal A and PCM terminal 2E
  • PCM connector or terminals malfunction
  • Open circuit in wiring harness between OCV terminal A and PCM terminal 2E
  • OCV malfunction
  • PCM malfunction
G07878136
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 8.
No Go to the next step.
3 INSPECT OCV POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT 
  • OCV connector is disconnected.
  • Turn the ignition switch to the ON position (engine off).
  • Measure the voltage between OCV terminal B (wiring harness-side) and body ground.
  • Is the voltage B+  ?
 Yes Go to the next step.
No Inspect the OCV related fuse.
  • If the fuse is melt:
    • Repair or replace the wiring harness for a possible short to ground.
    • Replace the fuse.
  • If the fuse is deterioration:
    • Replace the fuse.
  • If the fuse is normal:
    • Repair or replace the wiring harness for a possible open circuit.

Go to Step 8.
4 INSPECT OCV CONTROL CIRCUIT FOR SHORT TO GROUND 
  • OCV connector is disconnected.
  • Turn the ignition switch off.
  • Inspect for continuity between OCV terminal A (wiring harness-side) and body ground.
  • 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:
Go to Step 8.
No Go to the next step.
5 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 8.
No Go to the next step.
6 INSPECT OCV CONTROL CIRCUIT FOR OPEN CIRCUIT 
  • OCV and PCM connectors are disconnected.
  • Turn the ignition switch off.
  • Inspect for continuity between OCV terminal A (wiring harness-side) and PCM terminal 2E (wiring harness-side).
  • 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 8.
7 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.
8 VERIFY TROUBLESHOOTING OF DTC P1680 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.
9 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.
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