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What are the typical error codes associated with the 2020 Toyota Highlander? - Toyota Highlander
Home/Cars/Toyota/Highlander/Fourth Generation (2020-present)/What are the typical error codes associated with the 2020 Toyota Highlander?

What are the typical error codes associated with the 2020 Toyota Highlander?

Toyota Highlander Fourth Generation (2020-present)

Error Codes
medium
Difficulty
medium
Severity
Navigation
ProblemSymptomsDiagnosisSolution
ProblemSymptomsDiagnosisSolution
4 min read
647 words

Problem Statement

Explore typical diagnostic trouble codes (DTCs) for the 2020 Toyota Highlander, including symptoms, diagnostic steps, and tools required for effective repairs.

Affected Component
various systems

Symptoms

  • •Check Engine Light (CEL) illuminated
  • •reduced fuel efficiency
  • •potential rough idle
  • •possible fuel odor
  • •decreased fuel efficiency
  • •rough engine idle
  • •poor acceleration
  • •reduced power
  • •increased emissions
  • •harsh or erratic shifting

Diagnostic Steps

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9
  10. 10
  11. 11

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
  • •Multimeter
  • •Basic hand tools (sockets, wrenches)
  • •Vacuum gauge (if checking for vacuum leaks)
  • •Torque wrench (for reassembly)
  • •Safety equipment (gloves, goggles)

Additional Information

Affected Component
various systems
Difficulty
medium
Severity
medium
Tools Required
6 items

Related Faults

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Back to Generation

The 2020 Toyota Highlander, part of the fourth generation (XU70), can generate various diagnostic trouble codes (DTCs) related to different systems in the vehicle. Below is a list of typical error codes associated with this model, along with their meanings and potential symptoms.

Common Error Codes for the 2020 Toyota Highlander

1. P0420 - Catalyst System Efficiency Below Threshold (Bank 1)

  • Symptoms: Check Engine Light (CEL) illuminated, reduced fuel efficiency, potential rough idle.
  • Diagnostic Steps:
    • Use an OBD-II scanner to confirm the code.
    • Inspect the exhaust system for leaks prior to the catalytic converter.
    • Check the condition of the catalytic converter and oxygen sensors.

2. P0455 - Evaporative Emission Control System Leak Detected (Large Leak)

  • Symptoms: Check Engine Light illuminated, possible fuel odor, decreased fuel efficiency.
  • Diagnostic Steps:
    • Use an OBD-II scanner to read the code.
    • Inspect the gas cap for proper sealing and cracks.
    • Check the EVAP lines and charcoal canister for damage.

3. P0300 - Random/Multiple Cylinder Misfire Detected

  • Symptoms: Rough engine idle, poor acceleration, reduced power, and increased emissions.
  • Diagnostic Steps:
    • Use an OBD-II scanner to confirm the code.
    • Check for any misfire codes (P0301-P0306) that may indicate specific cylinder issues.
    • Inspect spark plugs, ignition coils, and fuel injectors.

4. P0171 - System Too Lean (Bank 1)

  • Symptoms: Check Engine Light illuminated, rough idle, and poor acceleration.
  • Diagnostic Steps:
    • Use an OBD-II scanner to confirm the code.
    • Inspect for vacuum leaks in hoses and intake manifold.
    • Check the fuel pressure and mass airflow sensor (MAF) operation.

5. P0717 - Input/Turbine Speed Sensor A Circuit Range/Performance Problem

  • Symptoms: Harsh or erratic shifting, Check Engine Light illuminated.
  • Diagnostic Steps:
    • Use an OBD-II scanner to read the code.
    • Inspect the input speed sensor and wiring for damage.
    • Check transmission fluid level and condition.
Tools Required
  • OBD-II Scanner
  • Multimeter
  • Basic hand tools (sockets, wrenches)
  • Vacuum gauge (if checking for vacuum leaks)
  • Torque wrench (for reassembly)
  • Safety equipment (gloves, goggles)
Repair Instructions (Example: P0455 - Evaporative Emission Control System Leak Detected)

  1. Gather Tools:

    • OBD-II scanner, basic hand tools, safety equipment.

  2. Scan and Verify:

    • Connect the scanner to the OBD-II port and retrieve the DTCs.
    • Confirm P0455 is present.

  3. Inspect the Gas Cap:

    • Remove the gas cap and inspect for damage or improper sealing.
    • Replace if necessary.

  4. Check EVAP System:

    • Inspect the EVAP hoses for cracks or disconnections.
    • Check the charcoal canister for damage.

  5. Perform Smoke Test:

    • If necessary, perform a smoke test to identify leaks in the EVAP system.

  6. Repair or Replace Components:

    • Repair any damaged hoses or replace the charcoal canister as needed.

  7. Clear Codes and Test:

    • Clear the DTC using the scanner.
    • Test drive the vehicle to ensure the light does not return.

  8. Final Inspection:

    • Recheck for any codes after the test drive and ensure all systems are functioning properly.

By following the above structured approach, you can effectively diagnose and repair common issues associated with the 2020 Toyota Highlander.