The Nissan Club banner

2009 Altima AC not working

44K views 68 replies 7 participants last post by  Fsanchez 
#1 ·
Hello. I have researched this problem and tried a few things before posting here but now need some help. First off, the blower works, the AC light comes on, it just blows no cold air whatsoever. I noticed this in the winter and it blew very cold air air last time it worked but I just put it off until now and will need AC again soon. Anyways, I checked the fuse under the hood and it is good. I tested the the contacts where I pulled the fuse out of and it is getting power when the AC button is on so it is good there. Then I pulled the connector going into the compressor and am getting no power there when the AC is on, so I believe this sounds like an electrical issue rather than a compressor issue. I read about checking relays and found them on the backside of the fuse panel on the driver's side under the dash, but I have no idea how to get to them. First off, is this where I should check next, and if so, how do I access them?
 
#2 ·
Hello and welcome. I too have an '09. My first jump would be to run through the diag process in the FSM (links in my .sig). It is possible that a high or low pressure sensor could cause the control system to not activate the electric clutch of the compressor, so it's not quite as cut and dried as you wrote above.

Start with the diag flow on page HAC-84 and let me know how you make out.

*THIS FREE HELP PROVIDED WITH THE EXPECTATION THAT YOUR DISCOVERIES AND CONCLUSIONS ARE SHARED WITH THE FORUM*
 
#4 ·
Hello. I apologize for posting this and not replying for awhile. I got really busy all of a sudden then was away on vacation for a couple weeks and finally have a chance to mess with this. Anyways, I performed the test that 08AltimaDriver suggested and the magnet clutch does not engage which I did not expect it to since it is not getting power at the harness. I looked through the service manual you gave me and the Magnetic Clutch section starting on page 46 seems to apply. So following the procedure on page 47, my question is how to access the relay in the IPDM? (Correct me if I am wrong, but is that the white fusebox under the dash?) It appears the relays are behind it, right? How do I get to them? Once I can access that, I can do the testing.
 
#3 ·
A quick and easy way to see if the magnetic clutch can be energized is to do the self-test.
This vid explains it fairly well. You'll hear a quick blast of the horn when it starts. It runs the various lights of the car, rad fan etc, but it will also energize the clutch at some point, regardless of system pressure. This test works with the engine off so there is no risk of running the compressor with low refrigerant. You'll hear a definite thunk sound when the clutch energizes, so if it doesn't then you have issues with the coil or its circuit.

https://www.youtube.com/watch?v=ww-mXgfEQPAhttps://www.youtube.com/watch?v=ww-mXgfEQPA
 
#5 ·
The IPDM is a large black box above and to the right of your battery in the engine compartment, beside the air filter housing (Gen4's). Lid unclips (front and back), and there is usually a fuse label map printed on the inside of the cover.
 
#9 ·
#11 ·
Yes, the 'white thing' is just a robust plastic case over a circuit board that the fuses plug into and the relays are soldered into. IF you were to split apart the white cover, you would then have access to the signals at the AC relay. I'm going to guess that Nissan has made that somewhat less than easy to do however. If you truly suspect the relay, then you can buy a second hand IPDM for about the cost of the diagnostics fee at the dealer, if you're wrong, at least there is some residual value in that investment.
 
#12 · (Edited)
Ok, so a couple things here.... I want to mess around with this a little bit because I love a challenge and trying to figure things out. But, it is also starting to get hot out and I can't go too long without this A/C so I may have to bring it in if I can't figure it out. Let me run this by you:

First off, can I just jumper some power from my battery to the compressor to verify the clutch is working? Will that verify it by running a positive and ground directly to it with the engine off? Will I hear it engage?

Secondly, if that does work, then I would assume it is an electrical problem somewhere between the fuse and the compressor (either a relay or sensor). Would I just need to pull the connector out of the IPDM and test the pins like the manual says? Are those connectors labeled somewhere in the IPDM (like connector F10 or M18 that it mentions to pull)? I suppose this could narrow it down a little bit, but I can't test the pressure in the system so it probably won't do me much good because if that is low, then the pressure system could just be doing it's job, right? Does someplace like AutoZone or O'Reilly's do free testing of that? Once I do all this, I guess I could take a chance and buy a used IPDM on ebay like you mentioned. I could always resell it if that wasn't the problem. Is that just a matter of unplugging all the harnesses, pulling out the IPDM, and swapping it with the new one?
 
#15 ·
Just reporting back on this, I tested the pressure and it is reading 80 on each side with it off so it is not low. I don't know what to do now. It sounds like there are many different electrical possibilities it could be. I am probably going to have to take it in aren't I? If so, is this something any mechanic should be able to troubleshoot, or am I better off bringing it to an electrical or AC specialist or dealership?
 
#16 ·
Have you checked voltage at the clutch during self test? Have you directly applied battery voltage to the clutch contact? Have you measured resistance of the clutch coil to ground? I only ask as we've talked about debugging the coil and I haven't seen any test results. It would help to know if:

1. coil is good or bad
2. harness can supply 12V when told to

You clearly still have refrigerant and a pressurized system, so it's most likely something electronic as opposed to mechanical.
 
#23 ·
Hi again. Ok, I apologize for the runaround as as I was wrong the first time. I ran the self test with a volt meter connected to the harness while it was unplugged and got voltage. Then I checked the harness again normally with the engine running and the AC button on and got voltage. So apparently I didn't get the tester far enough into the connector the first time around. Looks like the electrical side of it is fine then and this is a clutch issue. As far as the clutch, I don't think I can get my hands down there to jumper it as it is at at a weird angle reaching down from the top, but if it is getting voltage when it is on, I don't need to do this anyways, do I? Anyways, this means replacing the whole compressor, right? And if so, I can't really do it myself because I can't capture and refill the refrigerant, right? Let me know if I am missing something here or have other options. I appreciate all the help.
 
#17 · (Edited)
I have not checked these. I will try to get to it this weekend. Just seems so hopeless if it is electrical because there are so many things to check, but I won't give up yet. I remember the harness being hard to pull so hopefully I will be able to access the connector on the compressor to put some power to it. I'll let you know what I come up with. So to be clear, what exactly am I testing for the resistance of the clutch coil to ground? Where am I running the ohmmeter and what am I looking for? And just to expedite things, let's just say the clutch works when I apply voltage and the harness is not showing any voltage during the self test. If those two things occur, what do you suggest next? I appreciate the help. Have a great weekend.
 
#18 ·
YEs, coil resistance to ground should be >0 and less than say 500 ohms

If clutch actuates when direct voltage is applied, but the self test cannot provide any voltage pulses (I think it pulses it 5x?), then you can safely assume the issue is from the IPDM to the clutch...so I'd start with fusible links and fuses (think you covered those already), then I'd probe clutch wire where it plugs into the IPDM to see if the self test pulse are present there (if yes ,fuses and relay good harness bad), if no the relay/IPDM is bad. or that's my reasoning.
 
#21 ·
Thanks...pretty sure my Gen3 only had 1 wire, but I'm sure Nissan had their reasons for 2--just haven't had to disconnect the Gen4's yet.
 
#24 ·
Couple of things...I assume your '09 is a 2.5?

Also, have you been doing all this testing from the top (ie open hood)? If so, you probably should pull the front passenger wheel and remove the black plastic shield held on by 5 poppers that will expose the flywheel, belt and AC compressor. You may be able to get enough access like this, but if not, you can remove the splash undershield and then you'll be able to reach in from a number of angles to get at things. You can monkey around a fair bit if you are just measuring resistance...because it doesn't matter which way your probes connect to the coil contacts, of if they short together, or touch something. Eventually you should be able to get a probe on both contacts and verify that the coil has some resistance (not zero or infinite).

Now, you really should not be servicing compressors without the right equipment...and it's not just the environment i'm trying to protect here... That said, read through these threads:

http://www.nissanclub.com/forums/20...-5/480202-2008-c-clutch-stopped-engaging.html

http://www.nissanclub.com/forums/20...altima-ac-not-working-compressor-problem.html

(As discussed above) You CAN just replace the clutch unit...it's not pleasant, but can be done without discharging the AC system.
 
#27 · (Edited)
I gave it one more shot tonight and think I got something. I could turn the connector a little bit so I could see the pins straight down and am pretty confident I could see and feel the probes touching them and I got no continuity between the two (getting the OL). At the advice of someone else, I also tested the power connector again with the AC on and put the ground probe to the other pin in the connector as opposed to the battery ground to make sure the connector ground is ok and it is. I also was able to turn the clutch plate by hand to make sure the compressor is not locked up. So from this, are you still pretty confident it is just the clutch that is bad?

I watched the video that 08AltimaDriver posted and it actually does not look too bad as long as you can get that bolt out. Any advice on that? From what I read in other posts, sounds like it is nearly impossible to remove. Do I just need that clutch coil in the link you posted, or do I need the whole clutch kit with the plate and everything else that I have seen in other videos, etc.? What about the bolt (since it sounds like it may get damaged during the removal)?

If I brought this in to a shop, I am sure they would want to replace the whole compressor and that would probably be close to $1000. If it is probably just the clutch and all I need is that $28 part you mentioned, it is definitely worth giving this a try myself.
 
#25 · (Edited)
#28 ·
Well, we are pretty confident the coil is done and we know that remove the compressor is $$$.

If it was me, I'd have a go, not much to lose. Based on the horror stories of getting the bolt out, I might try something a little radical to improve my chances and I think I'd get a shop to spot weld a section of allen key, or even a proper hex key socket into the bolt before even starting to try to remove it. Then you can get a proper socket wrench on the thing. Because, once it's rounded off, you're pooched. Once it's out, sounds like the only other odd thing you need are some big spring clip / cir-clip pliers. Once out you can decide if you need the rest of the clutch or not, but I'd risk the $30 just to have it on hand, as opposed to waiting a few days for the full assembly. Even buying the spring clip pliers, you're probably well under a $100 in parts vs $1000.
 
#29 ·
Great point, it is definitely worth a shot for $30. I even have a snap ring tool (for some reason!). I think I'll order that and pull the wheel off and take a look. Having a shop weld a hex head on it is a good idea, but would involve bringing it to a shop and would take them some time to pull the wheel off, etc. I might try grinding a groove like in the video if it comes to that. Worst case if I can't get it off, it won't matter to the shop if they replace the whole thing anyways. I am curious though why this is a $1000 process. I have seen compressors for under $300 at Autozone or O'Reilly. Do shops just use the more expensive OEM compressors?
 
#30 ·
It's usually double the hardware cost to cover labour/recovery of the refrigerant. Plus, I have a VQ, so extra parts have to come out to get the compressor out. Just saying it's way more than a couple of hundred once that compressor comes out.

FYI the OEM is just a Valeo 171c compressor.
 
#31 ·
Ok I think I am going to try this. I just called a shop and they were very nice and informative. I got a price of $800 to replace the compressor and $1300 to also replace the drier and expansion device (just thinking ahead in case I screw it up). I was also surprised at how much advice he offered. He said they don't do the clutches because they are hard to get off and sometimes break the compressor anyways, but also suggested to me that replacing the compressor is not that difficult and I could probably attempt it myself and they would recharge the system. I am really tempted to do that now because it looks A LOT easier than the clutch. What do you think? If not, I could still attempt the clutch and if I screw it up, then maybe do the compressor?. I did a little more research and someone said they heated that bolt with a torch first and it came off easier.
 
#32 ·
Here's what I'd do. I'd buy a suitable sized quality hex key or hex key socket. I'd remove the splash guard and take it to my friendly muffler shop. I'd pay for 0.5-1hr of labour to put it up on a hoist, turn the wheels full to the right and have them tag weld the 3/4" or so of hex key directly onto that clutch bolt (need to check the clearance for what makes sense). then I'd get them to air impact wrench it out, antiseize it and put it gently back in. I'd drive home with the AC OFF! I am now ready to remove the clutch and replace the coil. $60 or so in labour, $30 or so in parts and the pure friggin' satisfaction of beating the 'man'.... I'd replace that bolt with a standard one and maybe a little blue loctite.

Worst that can happen is they can't get it out and have to cut it off again. You are out maybe $60? and can go back to recovering the R134a and replacing the compressor yourself plan.
 
#35 ·
Ok, one more series of questions before I do this because I probably won't tackle this until later next week when I know I can get by without the car for a few days in case I screw something up:

Replacing the clutch: I am going to try this first. I think I will first see if I can get it off myself applying heat because I see where someone managed to do that. If that doesn't work, I will cut the groove like the in video. If I still can't get it out, I will check to see if a shop can weld a hex head on it. So if I do get this off, I just want to confirm that everything comes out without a hub puller or any other special tools (besides the snap ring pliers). In the video, it looks like it all just comes out but I want to make sure. Another thing I saw about clutches while doing more research was something about shims. Do I need to measure a gap distance or anything, or just put it all back together the way it was? Any details on that would be appreciated.

Replacing the compressor: If I do totally screw it up and can't get it off and have to go this route, I have a couple questions. I watched the video posted by the same user that did that clutch replacement in the Altima and it looks pretty easy. My first question is, is it really necessary or a good idea to replace the drier and expansion device at the same time? The drier looks pretty easy to get to but the expansion device is a little more buried. The second question is about flushing and vacuuming the system. I am a little confused about that part. I understand the refrigerant has to be evacuated first, but when does the flush occur? Do they do that when they recharge the system, or is it done when it is open? And do I add the oil to the compressor when I install it (the amount listed on the sticker inside the hood), or will that get evacuated out during the vacuum process? And I imagine it is safe to drive when the system is empty (it won't engage anyways because the sensor will detect no pressure, right)? Sorry for all the questions in advance, most of which probably won't apply, but I just want to be prepared in case I need to do these steps. Thank you so much for all your help.
 
#33 ·
Anyone else seeing the thread as if it were on a website from 1993? Forum showing the threads looks ok but when I go in to this thread it's pretty much plain text. This just started happening yesterday. Pretty much like if you see a web page intended for mobile devices but see it on desktop.
 
#34 ·
Yes, me too, and it's only on page 3 of the thread?!
 
#36 ·
I'm ok with the escalation approach to bolt removal, might want to soak that bolt head with penetrating oil serveral times over a couple of days in advance, also might want to add some mechanical shock after the heat (hammer taps). Super curious to find out how you get it done!

As for the compressor replacement. Usually you only replace the drier when you've had no refrigerant (zero pressure) for more than couple of hours as the drier chemical will quickly get used up by atmospheric humidity. You also do the drier and expansion valve when you've had a compressor failure...so metal filings are loose in the system and without flush will cause new compressor to fail in short order. For commercial refrigeration, they would typically 'flush' with a nitrogen charge as it acts as a drying agent, removing any moisture in the system, and then fill with the proper amount of R134a and compressor oil. I would get a pro to do the flush and recharge. Don't forget to use all new o-rings rated for R134a.
 
#37 ·
Good idea with the oil. So a rapid blow to the wrench might be better than trying to move it slowly? Good to know.

For the compressor replacement, are you saying I should do the drier too then since it will be without refrigerant for more than a few hours but the exp valve will be ok? So would I just install the compressor (and drier possibly), replace the o-rings for the parts I take apart, and just put everything together and let the pro take apart what they need to in order to do the flush? Since the compressor doesn't get flushed, I am good putting the oil in it then, right?
 
#38 ·
Don't hit the wrench! Use a flat punch and directly hit the interior of the bolt (or an anti-bolt since it has a hex-void instead of a hex-head...). Idea is shock the threads and loosen up rust/seizing/corrosion whatever making it easier to back out. Hitting your wrench while it's seated in that super shallow hex opening is pretty much guaranteed to strip it first time. You could also use something like a 10mm socket to distribute the hammer blow around the head of the bold without damaging the hex facets. In that case, hold the socket flush to the face of the bolt and strike the socket sharply with a hammer.

If you only have the system open for a couple of hours you are probably fine with leaving the drier (unless you are in Humi-Houston). If no leak or failure I see no reason to change out any parts. If you take the compressor hoses off and then get stuck for a couple of days....either put it all back together to limit the amount of moisture that can sneak in, or plan to replace the drier after all.

I would leave the oil addition up to the pro's...you don't want too much or too little...and they likely won't warranty their work unless they have control over what's gone in.
 
#39 ·
Looks like you may need a puller--see the mag clutch section at the end. This isn't the same exact family of compressors, but all Valeo's are similar that have mag clutches on them.
 
#40 ·
Looks like I can borrow a puller from Autozone. FYI, I found a complete clutch kit on ebay for $50 so I just bought that instead. I will probably hold off on this until the 4th of July weekend because I am going to be home and won't really need the car that entire week after the 4th either in case I totally screw it up. I'll keep you informed when I tackle this. Thanks again.
 
#43 ·
I just received the clutch today. Would you mind taking a look at these pictures? There is a small dent at the edge of the pulley and I am just wondering how close the belt rides to the edge or if this may affect anything. Do you think this looks ok?


 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top