why does my Toyota Highlander Third Generation (2014-2019) AC not blowing cold air

Toyota Highlander Third Generation (2014-2019)

Error Codes

2-4 hours

Time

medium

Difficulty

medium

Severity

4 min read

665 words

Problem Statement

Learn how to diagnose and fix AC not blowing cold air in Toyota Highlander (2014-2019). Step-by-step guide with diagnostic procedures and repair instructions.

Affected Component

HVAC

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 working on.

Symptoms

•AC blows warm air instead of cold
•Unusual noises from the AC compressor
•AC compressor not engaging
•Condenser or evaporator frost buildup
•"Check AC" warning light illuminated on the dashboard
•Decreased airflow from the AC vents

Diagnostic Steps

1
Scan for error codes using an OBD-II scanner to check for AC system-related codes.
2
Inspect the AC refrigerant level using a pressure gauge to determine if it is low.
3
Check the AC compressor operation by observing whether it engages when the AC is turned on.
4
Inspect the AC fuses and relays for any blown components.
5
Examine the AC system for visible leaks or signs of oil around the compressor, hoses, and connections.
6
Verify the condition of the cabin air filter to ensure it is not clogged.

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
•AC refrigerant kit
•Pressure gauge
•Multimeter
•Socket set
•Torque wrench

Parts Required

•AC refrigerant
•AC compressor (if needed)
•Cabin air filter

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 check for AC system-related codes.
2
Inspect the AC refrigerant level using a pressure gauge to determine if it is low.
3
Check the AC compressor operation by observing whether it engages when the AC is turned on.
4
Inspect the AC fuses and relays for any blown components.
5
Examine the AC system for visible leaks or signs of oil around the compressor, hoses, and connections.
6
Verify the condition of the cabin air filter to ensure it is not clogged.

Solution

1. Preparation

Gather necessary tools and parts.
Ensure the vehicle is parked on a level surface and the engine is off.
Disconnect the battery to avoid any electrical issues during repair.

2. Recharge Refrigerant

Tools Required: AC refrigerant kit, pressure gauge
Check the refrigerant level using a pressure gauge. If low, follow these sub-steps:
1. Attach the refrigerant can to the low-pressure service port.
2. Start the engine and turn on the AC to the maximum setting.
3. Slowly open the refrigerant can valve to allow refrigerant to flow into the system.
4. Monitor the pressure gauge to ensure it reaches the recommended level (typically around 30-40 psi for low pressure).
5. Disconnect the refrigerant can and replace the service port cap.

3. Inspect and Replace AC Compressor

Tools Required: Socket set, torque wrench
If the compressor is not engaging, follow these steps:
1. Locate the AC compressor and inspect the electrical connector for corrosion or loose connections.
2. If the connector is fine, use a multimeter to test the compressor clutch for continuity.
3. If no continuity is found, replace the AC compressor:
  - Disconnect the refrigerant lines carefully and recover any remaining refrigerant.
  - Remove the mounting bolts of the AC compressor and detach it from the engine.
  - Install the new compressor by reversing the removal procedure and torque bolts to the manufacturer’s specifications.
  - Reconnect the refrigerant lines and ensure all connections are tight.

4. Replace Cabin Air Filter

Tools Required: None
If the cabin air filter is clogged:
1. Locate the cabin air filter compartment (usually behind the glove box).
2. Remove the filter cover and take out the old filter.
3. Install a new cabin air filter according to the directional airflow markings.
4. Reattach the filter cover.