why does my Toyota Highlander XU70 (2020-Present) coolant keep running low

Solution

1. Preparation

• Gather tools and parts.
• Park the vehicle on a level surface and allow the engine to cool completely.
• Disconnect the negative battery terminal to ensure safety.

2. Inspect and Repair Leaks

• Tools Required: Pressure tester, socket set, hose clamps
• Sub-steps:
  1. Use a pressure tester to pressurize the cooling system; look for leaks.
  2. If leaks are found at the radiator or hoses, replace damaged components:
     • For hoses, loosen the clamps, remove the old hose, and install the new hose securely.
     • For the radiator, remove mounting bolts, disconnect hoses, and replace with a new radiator.
  3. Replace the radiator cap if it is not sealing properly.

3. Inspect Water Pump

• Tools Required: Socket set, coolant catch basin
• Sub-steps:
  1. Remove the engine cover if necessary for access.
  2. Inspect the water pump for any signs of coolant leakage around the pump shaft.
  3. If leaking, remove the water pump using a socket set, clean the mounting surface, and install a new water pump with the appropriate gasket.
  4. Refill the cooling system with the proper coolant mixture.

4. Check Head Gasket (if needed)

• Tools Required: Torque wrench, gasket scraper
• Sub-steps:
  1. If coolant is found in the engine oil, prepare to replace the head gasket.
  2. Remove the cylinder head following the service manual procedure; keep track of bolt locations and orientations.
  3. Clean the cylinder head and engine block surfaces thoroughly.
  4. Install a new head gasket and reassemble the cylinder head, torqueing the bolts to manufacturer specifications.