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How to resolve the gear shifting issues in a 2021 Toyota Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/How to resolve the gear shifting issues in a 2021 Toyota Highlander?

How to resolve the gear shifting issues in a 2021 Toyota Highlander?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
2-4 hours
Time
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
4 min read
631 words

Problem Statement

Learn how to diagnose and fix gear shifting issues in a 2021 Toyota Highlander with our step-by-step guide.

Affected Component
transmission
Estimated Time
2-4 hours

Symptoms

  • •Delayed Shifting
  • •Slipping Gears
  • •Harsh Engagement
  • •Warning Lights
  • •Unusual Noises

Diagnostic Steps

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5

Solution

💡 Expert Tip

For complex repairs like this, consider taking photos at each step. This helps if you need to reverse a step or consult with a mechanic. Also, keep all removed parts organized - you may need to reference them during reassembly.

Verification

After completing the repair, verify that the issue has been resolved:

  • ✓Test the affected component to ensure it functions correctly
  • ✓Check for any error codes or warning lights
  • ✓Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

  • •Follow the manufacturer's recommended maintenance schedule
  • •Address warning signs early before they develop into major issues
  • •Use quality parts and fluids recommended for your vehicle
  • •Keep detailed records of all repairs and maintenance

Tools & Equipment Required

  • •OBD-II Scanner
  • •Transmission Fluid Dipstick
  • •Funnel
  • •Transmission Fluid (Toyota ATF WS)
  • •Torque Wrench
  • •Socket Set and Ratchet
  • •Pliers
  • •Shop Towels
  • •Jack and Jack Stands

Additional Information

Affected Component
transmission
Estimated Time
2-4 hours
Difficulty
medium
Severity
medium
Tools Required
9 items

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Resolution of Gear Shifting Issues in a 2021 Toyota Highlander
Tools Required
  • OBD-II Scanner
  • Transmission Fluid Dipstick
  • Funnel (for adding fluid)
  • Transmission Fluid (Toyota ATF WS)
  • Torque Wrench
  • Socket Set and Ratchet
  • Pliers
  • Shop Towels
  • Jack and Jack Stands (if needed for undercarriage access)
Repair Instructions

Step 1: Check and Change Transmission Fluid

  1. Ensure Vehicle is Level: Park the Highlander on a level surface.

  2. Check Fluid Level:

    • Remove the dipstick, wipe it clean, reinsert it and then remove it again to check the fluid level.

  3. Add Fluid if Necessary:

    • If low, add Toyota ATF WS fluid through the dipstick tube until the correct level is reached.

  4. Fluid Change:

    • If the fluid is dark or burnt, perform a fluid change:
      • Raise the vehicle using a jack and secure it with jack stands.
      • Remove the transmission pan bolts with a socket wrench.
      • Carefully lower the pan and drain the old fluid into a pan.
      • Replace the filter if applicable (depending on the design).
      • Reassemble the pan and torque the bolts to the manufacturer's specifications.
      • Refill with new Toyota ATF WS fluid.

Step 2: Address Error Codes

  1. Clear Codes: After checking and resolving any issues, clear the DTCs using the OBD-II scanner.
  2. Test Drive: Perform a test drive to ensure that the codes do not return and that shifting behavior is normal.

Step 3: Software Update

  1. Check for Updates: If the vehicle is within warranty, consult with a Toyota dealer about any available software updates for the TCM.
  2. Perform Update: Follow the dealer’s instructions to update the software if applicable.

Step 4: Inspect Transmission Components (if issues persist)

  1. Inspect Transmission Solenoids:

    • Access the transmission control solenoids, usually located on the valve body.
    • Check for proper operation using a multimeter or by substitution if necessary.

  2. Check Wiring and Connectors:

    • Inspect wiring harnesses and connectors to the transmission for damage or corrosion.

  3. Transmission Control Module (TCM):

    • If all else fails, consider testing or replacing the TCM as a last resort.
Conclusion

After performing the above diagnostics and repairs, monitor the vehicle for any recurring symptoms. If problems persist, consider seeking assistance from a professional mechanic or a Toyota dealership, as deeper issues with the transmission may require specialized tools and expertise.