I have a 2005 Honda Accord Hybrid and seems to be having the following problems with the Air Conditioning.

- Sometimes when the AC is on while driving, I hear a sound as if a motor is running in the engine and the engine seems to be taking a little load. Shortly thereafter the sound goes away and the engine no longer feels to be taking that extra load.

- Also sometimes, when I stop at a red light, the cooling goes down and the air become warm but as soon as the car moves, the air becomes cool again.

- The front defroster won't defrost with the engine running when the car is not moving but as soon as you start driving, it defrosts fine.

What could be the problem?

 

Not an a/c expert, but all of my R134 cars lose cooling ability at idle. The compressor needs to be at a higher speed to work efficiently (this goes for the defroster too...). Also, if you have to be driving to get the defroster to work, check your a/c settings to make sure the "recirculation" button is engaged. HTH