why does my Toyota Highlander Third Generation (2014-2019) have delayed shifting

Toyota Highlander Third Generation (2014-2019)

Error Codes

2-4 hours

Time

medium

Difficulty

high

Severity

3 min read

591 words

⚠️ Safety Warning

This issue requires immediate attention. If you are not experienced with automotive repairs, consult a professional mechanic. Working on critical systems can be dangerous.

Problem Statement

Learn how to diagnose and fix delayed shifting issues in Toyota Highlander (2014-2019). Step-by-step guide with diagnostic procedures and repair instructions.

Affected Component

Transmission

Estimated Time

2-4 hours

⚠️ Safety Warnings

Important safety information - read before proceeding

•Disconnect the battery before working on electrical systems.
•Allow the engine to cool before opening the transmission fluid pan.

Symptoms

•Noticeable delay in gear engagement during acceleration
•Harsh or erratic shifting between gears
•Engine RPMs increasing without corresponding vehicle speed
•Check engine light illuminated
•Slipping transmission or loss of power during driving
•Fluid leaks under the vehicle

Diagnostic Steps

1
Scan for error codes using an OBD-II scanner to identify any transmission-related issues.
2
Check the transmission fluid level and condition; inspect for contamination or burnt smell.
3
Inspect the transmission control module (TCM) for proper function and connections.
4
Test the throttle position sensor (TPS) for proper voltage output and functionality.
5
Inspect the engine air filter and Mass Air Flow (MAF) sensor for blockages or dirt.
6
Examine the vehicle's battery voltage and charging system to ensure proper electrical supply to the transmission.

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
•Socket set
•Fluid pump
•Catch pan
•Multimeter

Parts Required

•Transmission fluid (ATF WS)
•Transmission filter (if applicable)
•Throttle position sensor (if faulty)
•Transmission pan gasket

Related Faults

Share this solution

Comments

No comments yet

Be the first to share your thoughts

Back to Generation

Diagnostic Steps

1
Scan for error codes using an OBD-II scanner to identify any transmission-related issues.
2
Check the transmission fluid level and condition; inspect for contamination or burnt smell.
3
Inspect the transmission control module (TCM) for proper function and connections.
4
Test the throttle position sensor (TPS) for proper voltage output and functionality.
5
Inspect the engine air filter and Mass Air Flow (MAF) sensor for blockages or dirt.
6
Examine the vehicle's battery voltage and charging system to ensure proper electrical supply to the transmission.

Solution

1. Preparation

Gather necessary tools and parts.
Park the vehicle on a level surface and engage the parking brake.
Disconnect the battery to ensure safety while working on electrical components.

2. Transmission Fluid Check and Replacement

Tools Required: Socket set, fluid pump, catch pan
Remove the transmission fluid dipstick and check fluid level.
If low, add the correct type of transmission fluid (typically ATF WS for Toyota).
If fluid is discolored or burnt, proceed to replace it:
1. Place a catch pan under the transmission pan.
2. Remove the transmission pan bolts using a socket set.
3. Carefully lower the pan and allow old fluid to drain completely.
4. Replace the transmission filter if applicable.
5. Reinstall the pan with a new gasket, tightening bolts to manufacturer specifications (usually 8-10 ft-lbs).
6. Refill the transmission with new fluid through the dipstick tube.

3. Inspect and Test Transmission Control Module (TCM)

Tools Required: Multimeter
Locate the TCM, typically found near the transmission or under the dashboard.
Check electrical connections for corrosion or damage.
Use a multimeter to test for proper voltage and ground at the TCM connectors.
If faulty, replace the TCM by disconnecting the battery, removing the old module, and installing the new one.

4. Throttle Position Sensor (TPS) Testing and Replacement

Tools Required: Multimeter, socket set
Locate the TPS on the throttle body.
Disconnect the electrical connector and use a multimeter to check resistance across the terminals.
If readings are out of specification, replace the TPS.
Reinstall the new sensor and reconnect the electrical harness.