DTC Troubleshooting: P1684 (40)
DTC P1684:
 ISV Return Spring Performance Problem
Do not insert your fingers into the installed intake shutter valve when you turn the ignition switch ON (II) or while the ignition switch ON (II). If you do, you will seriously injure your finger if the intake shutter valve is activated.

NOTE: Before you troubleshoot, record all freeze data and review the general troubleshooting information.
  1. Turn the ignition switch ON (II).
  1. Clear the DTC with the HDS.
  1. Start the engine.
  1. Turn the ignition switch OFF, and wait 1 minute.
  1. Start the engine.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P1684 indicated?
YES -
Go to Step 7 .
NO -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the intake shutter valve and the ECM.■
  1. Turn the ignition switch OFF.
  1. Disconnect the intake air duct from intake shutter valve.
  1. Push the intake shutter valve closed as shown.
    NOTE:
    • Do not operate the ignition switch during the check.
    • Be careful not to pinch your fingers during the check.
  1. Release the intake shutter valve.
Does the valve return smoothly?
YES -
Clean the intake shutter valve, then go to Step 12 .
NO -
Go to Step 11 .
  1. Replace the intake shutter valve.
  1. Turn the ignition switch ON (II).
  1. Reset the ECM with the HDS.
  1. Start the engine.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P1684 indicated?
YES -
Check for poor connections or loose terminals at the intake shutter valve and the ECM, then go to Step 1 .
NO -
Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.■