How to replace the heater water pipe and exhaust the air in the Audi Q7. What is the method to replace the heater water pipe and exhaust the air in the Audi Q7?

1. Unscrew the water tank cover, open the water tank drain valve, and release the antifreeze.

2. Insert a rubber tube connected to the tap water pipe into the water filling port of the water tank, open the tap, and allow tap water to flow continuously through the engine cooling system. During the flushing operation, make the engine idle and maintain the above operation until clean water is released from the water tank.

3. Close the water faucet, wait until the water in the cooling system is drained, and then close the water tank drain valve.

4. Add antifreeze from the water filling port of the water tank so that the antifreeze fills the water tank. Unscrew the tank cap and add antifreeze until it reaches the "Max" mark. Be careful not to exceed the "Max" mark.