how often should A/C fan engage?

[tttP5]

is it normal when i have the A/C on and the car sitting at idle i hear the A/C fan (inside the engine compartment) come on for a duration of around 20 seconds every 30 seconds? it keeps switching between on and off.... i have no idea if it is like this when the car is driving because i do not have the door open so i can't hear the fan.

please post replies

[daKiNeP5]

My car does that too. Question: does your radio turn off then turn on right after when your fan goes on? I've been having that problem and after I turn off my car my alarm gets armed so the siren goes off when I open the door.

[tttP5]

my radio doesn't turn off then turn back on.

but my headlights do dim out for a split second, and this happens quite frequently.

i haven't done anything to my electrical system either.