Air conditioner and HVAC wiring diagrams

Roy,

My mechanic is telling me that other than that fuse (10a) there is a relay. I have tried searching and Googling it and cannot seem to find one. I just see that fuse. Do you know if there is any?
Thanks

Fuses replaced, all good, all three of them. The relay checks good. The blower motor was bad so motor is new. Reading 13.75 volts dc from hot to ground at motor connection and still motor does not turn. Put twelve volts to motor and it turns. Probably Controller circuit board? Operates variable speed by ground wire? I bought a new controller out of wrecking yard they said it worked. I installed the controller and still blower motor does not work. Checked fuses, swapped relays still no go. Are the sensors in series prior to the motor. I need the air conditioner wiring diagrams please.

The fan switch control for the AC/Heater comes on like clockwork about twenty to thirty minutes after driving the car. I have manual temperature controls and replaced the fan switch control assembly with no luck. I have had better success when I place a space heater in the car on the passengers side pointed towards the console for thirty minutes then remove it and start driving, the heater fan motor will start after only five minutes of driving, sometimes right away. It will run for hours once started and sounds perfect, but if I stop the car for an errand leaving it off for fifteen to twenty minutes, it will take fifteen to twenty minutes for it to come back on. During the summertime, it is the same pattern with the AC it will take five to ten minutes for the AC to come on, but winter time seems to take much longer. Heat only comes on ten to twenty minutes after running. I changed the blower motor got new one and still does the same thing. Can you please help me figure this out. I also brought it to my neighborhood service station and they do not know what is wrong with it either?

Please advise. Thanks!

Thanks for those. However, when I tried printing them they came out all blurry. I am unable to read the text at all. I tried saving them and printing from my desktop but that did not help. Is there anything you can suggest?

I have the same issue. The problem does not repeat itself when I drop it off at the dealership so they are unable to troubleshoot it.

I have a 2007 Nissan Altima. The issue began in November 2012 (just before the five year warranty ended). I woke up early to go to work, it was cold outside and the heating or A/C would not turn on. There is absolutely no noise or air blowing out of it. I have tried turning the car off and on again but this only works occasionally. After several minutes (two to ten minutes), the A/C and heating unit will start blowing air.

It seemed to happen more often last week when the temperatures were as low as the mid twenties at night.
The dealership changed the blower motor, control head, and recharged the A/C in November 2012.

Now, the warranty is expired and the dealership can not troubleshoot it. I took the car in Friday night and it worked perfect all day Saturday. And of course it acted up for us Sunday morning! It is difficult to get it to the dealership when it is acting up.

Anyone else been able to troubleshoot this issue?

I figured out the problem and solution We did exactly what you said and now we have heat any time we want it! The radio only works when it wants now, but we know how to fix that. Just have to buy new relay they are about $30.00.

Hi, I was able to fix the problem, the blower motor works great now. Here's what I did. That relay is located in the instrumental panel fuse box ( behind the fuse box). Remove the cover for the fuse box, you will see the fuses, unscrew one screw next to it, and there is one more screw to be removed, remove the panel below the steering wheel, it is very easy just pull it down. Now you have easy access to fuse box, on the other side of the box there are four blue identical relays ( part number ends on 42. There is about ten digits number). Relays are located like this. *__**__* ( relay 1, space, relay 2 relay 3, space, relay 4). Blower motor relay is relay 1. Ideally would be to replace it ( you can buy it at the dealership or online). What I did, I replaced relay 1 and relay 2 ( relay 2 is for radio), everything is working great both blower motor and radio, if one day radio stops working I know what to fix. But I need heater more than radio, specially living in Minnesota.

When driving home from work, fifteen minutes into the drive my AC just stopped working and was blowing hot air. I tried to add Freon but it seemed like the pressure was too high and the car was rejecting the Freon. I shined the flash light on the compressor and noticed it was not spinning/moving. I usually have bad luck at mechanic shops and getting ripped off, so my friend who is pretty knowledgeable about cars is helping me. I have spent hours trying to charge and diagnose. I am stuck and have no idea what to do next. Any Ideas to help?

Did you ever fix your problem with the AC/heater not turning on? If you did what was it?

Pressure sensor wires were damaged by a mouse. The wiring is repaired but A/C compressor still not engaging. I checked for power and grounds. At the A/C compressor relay all power sides are there but no ground is being command it to relay. Freon pressure is good Can it be the ECM nor BCM?

Scwickestang thank you for your help CPU was the problem.
Thank you for the diagrams and the time you spend to help me out you have saved me a large amount of money because I was about to replace the ECM and BCM.

My a/c will come on sometime will not, the air is getting cold when its on and go up to cycle stage when it reach the correct temp. Work fine, sometime when you turn off the car and sit for 30 min to 1 hour when you start back up and drive and turn on the a/c sometime it will not come on and I see the clutch engage for spit a second it trying to engage but it doeskin continue, I already replace the triple switch on the top of the dryer w/ 4 wires connector still the same make no deference and when I ground the red wire from the sensor it work but a/c always on even you off the a/c sw. What could be the problem? Can you give me the complete wiring diagram for air conditioning with the correct color coding and the location of ECM and the thermo control amp. Where they hide it. Thank"s fixsky