Toyota Corolla 2014 MIL “ON” DTC P2646 and/or P2658 Repair

Some 2014 model year Corolla vehicles equipped with the 2ZR-FAE engine may exhibit a MIL “ON” condition with either one or both of the following Diagnostic Trouble Codes (DTCs):

  • P2646 – A Rocker Arm Actuator System Performance or Stuck Off (Bank 1)
  • P2658 – B Rocker Arm Actuator Position Sensor Circuit Range Performance (Bank 1)

The Engine Control Module (ECM, SAE term: Powertrain Control Module/PCM) calibration has been revised . Use the following repair procedure to improve this condition.



Repair Procedure

1.Using Techstream, check for stored DTCs.

Are DTC(s) P2646 and/or P265B present?

–YES – Continue to step 2.

–NO – This bulletin does NOT apply. Continue diagnosis using the applicable Repair Manual.

2.Clear all DTCs, start engine in Park or Neutral, increase engine RPM to 3500 for 5 seconds.

Did the DTC(s) return?

  • YES – Continue to step 3.
  • NO – Continue to step 7.

3.With the vehicle in IG ON/Engine OFF, clear the DTC(s) that reset, then perform the Learn Value

Reset Utility (Engine and ECT -> Utility -> Learn Value Reset).

4.Reset connection cycle to ensure active test function.

A.Turn the ignition to IG OFF. If equipped with a standard key, remove the key from the ignition.

B.Disconnect Techstream from DLC and exit Techstream software.

C.Open Techstream software then connect Techstream to DLC.

D.Turn the ignition to IG ON. Do NOT start the vehicle at this time.

E.On Techstream, select Connect to Vehicle. Then select Engine and ECT, then choose Data List.

5.Perform the Engine Off VALVEMATIC Active Test.

A.Set up custom data list to show VALVEMATIC Target Angle and VALVEMATIC Current Angle.

B.Select Active Test Activate the VALVEMATIC (ENG OFF) and ensure parameters are met.

C.Perform active test LOW first (right arrow). Check for change to VALVEMATIC Current Angle (it should go to approximately 105 – 106 degrees).

D.Perform active test HIGH (it should climb above 108 degrees).

E.It may take more than one LOW and HIGH cycle attempt to get the numbers to increase or


6.After verifying VALVEMATIC Current Angle value changes, close Techstream software, start engine, and increase RPM to 3500 for 5 seconds.

Did the DTC(s) return?

–YES – Repeat steps 3 to 5.

— NO – Continue to step 7.


7.Check for the Authorized Modifications Label affixed to the vehicle in the location shown in Figure 1. Confirm if the ECM (PCM) calibration has been updated. If the calibration ID listed is

NOT the latest ECM (PCM) calibration – go to step 8.



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