DTC Troubleshooting: P1684 (40)

DTC P1684:  Throttle Valve Return Spring

Do not insert your fingers into installed throttle body when you turn the ignition switch ON (II) or while the ignition switch is ON (II). Otherwise, you will have serious injury to your fingers if the throttle body was activated.

NOTE: If DTC P0638 is stored at the same time as DTC P1684, troubleshoot DTC P0638 first, then recheck for DTC P1684.

1.Turn the ignition switch ON(II).

2.Do the DTC CLEAR in the CLEAR MENU with the HDS.

3.Do the ETCS TEST in the INSPECTION MENU with the HDS.

4.Check for Temporary DTCs or DTCs in the DTCs MENU with the HDS.

Is DTC P1684 indicated?

YES - Go to 5.

NO - Intermittent failure, system is OK at this time.Check for poor connections or loose terminals at the throttle body and at the ECM.n

5.Turn the ignition switch OFF.

6.Remove the air cleaner.

7.Push the throttle valve to open side as shown.

  • Do not operate the ignition switch during check.
  • Be careful not to pinch a finger during check.


8.Check the throttle valve.

Does a throttle valve return?

YES - Do the throttle body cleaning, then go to 11.

NO - Go to 9.

9.Turn the ignition switch OFF.

10.Replace the throttle body.

11.Install the air cleaner.

12.Turn the ignition switch ON (II).

13.Do the ECM RESET in the CLEAR MENU with the HDS.

14.Do the ETCS learn procedure.

15.Check for Temporary DTCs or DTCs in the DTCs MENU with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P1684 is indicated, check for sludge or carbon on the throttle bore again, then go to 11. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC troubleshooting.

NO - Troubleshooting is complete.n