How is the AC System related to the Alternator?



I just had the dealer replace my alternator. They said it would take 2 hours, but now they’re saying they had to pull out the AC system (to get to the alternator) and when they went to put it back in (after alternator was replaced) their Freon machine broke and I have to wait for another place to fill it up.

I thought they stopped putting freon into cars awhile ago? The dealer told me it would take 2 hours, but now I’m going on 6. My questions are:

1. Do you have to take the AC unit out to change the alternator?

1.a. If so, do you have to drain the freon?

2. What is the average price to have an alternator replaced?

3. Are there any potential issuescomplications with having your freon drained
eplaced that I should be aware of?

I have a 2001 Nissan Maxima SE with 105k miles. My car broke down while visiting family who live very far away; I’m stranded and forced to take it to the dealer.


The manager probably used the word “freon” in the generic sense.

Tell the manager you want to be escorted into the shop and shown why any AC component needed to be removed to get at the alternator.

Make sure they credit you for any “freon” they remove (don’t let them charge you for your own “freon”)


It would be rare to have to evacuate the A/C system. I was curious so I looked up the repair guide here-,2635701/initialAction,repairGuide/shopping/repairGuide.htm?pageId=0900c152801a3bc2#hd1-1-2 which clearly describes having to dismount and move the compressor forward to gain access to the alternator on some engine configurations. This does not require evacuation, only temporary relocation to gain access.

These guides can be misleading. Another scenario might be that, in a perfectly working scenario, it is easier for the mechanic if they just evacuate and disconnect the compressor and the labor savings ultimately being cheaper to the consumer but I doubt it.


Thanks oldschool!

I just talked to the dealer again and they said it was the AC Compressor that had to be removed to get to the alternator. I also asked specifically about freon and they said “yes, there is freon in my car; that’s what makes the AC cool”.

Does that make more sense or are they still yanking my chain?


Thanks TwinTurbo! That was a great link you posted; lots of good information there. It looks like the AC Compressor is listed as needing to be removed to get at the alternator. I’m not sure why they drained it, but I will find out!


It may be a matter of taste as to whether to try to muscle the alternator past the compressor or to completely remove the compressor. If the compressor is completely removed, the freon must be captured because it is not allowed be be vented to the atmosphere. Once reassembled, your system would normally be recharged with at least the same amount of freon that was removed. Oldschool mentioned “don’t let them charge you for your own freon,” and that is because freon is expensive.

I found the following on the Louisiana Department of Environmental Quality website:

The (federal) Clean Air Act prohibits knowingly venting ozone-depleting refrigerants (like Freon) while servicing or disposing of air conditioning/refrigeration equipment.