dnichols5053

I have replaced the fuse, relay and the ambient temperature sensor........and still NO air. The blower and controller module are new also. Still the
clutch on the pump is not engaging. Unless theres some other trick. I'm at a loss???

Slamrod

iTrader: (11)

dnichols5053

Thank you.....Will try on Monday.

DennisMik

iTrader: (2)

If you have the auto climate controls, you can run a self diagnostic. In case you do, here is a link to the instructions.

http://boredmder.com/FSMs/Nissan/Maxima/2001/HA.pdf

The procedure starts on page 37.

dnichols5053

A few days ago when the weather was up in the 70's I was on the highway had the car up to temp and decided to turn on the air. IT WORKED. So I must have some type
of sensor problem. I replaced the outside sensor two weeks back with no change. Its odd because the temp. readout in the gage always way lower than the outside temp. and then when you hit the AMB button
on the console its even lower. sometimes in the single digits. I haven't replace the interior sensor because I don't know where it is?? I did run the self diagnostics and the number were right on.??

DennisMik

iTrader: (2)

When you say blower, is this the fan that blows the air out of the dash ducts? If yes, does the fan blow air even though the a/c compressor is not running?

What gauge are you referring to? The temperature setting in the a/c control panel?

Sorry, I don't understand this. Could you re-word?

Below is a photo of a car with the radio removed. Look at the top item, the Cabin Temperature Sensor.

Amave

are both radiator fans working?

If not then what happens is without the fans blowing the pressure is too high thus causing the a/c pressure sensor to read too much pressure and making the PCM not engage the compressor

dnichols5053

The blower and all the ducts are working fine and the gage I refered to is in the RMP read out. It always say a low temp and shows "ICY".
And the the AMB readout is even lower. Thanks for the Picture but, now how to remove the radio(its aftermarket)

DennisMik

iTrader: (2)

Two people have asked questions about the a/c refrigerant pressure sensor. Have you had the refrigerant pressure checked and have you tried to test the pressure sensor? Your answers are ambiguous.

One thing than bothers me is that you ran the self diagnostic and said that it ran correctly but you keep getting incorrect readouts in the car. I am not sure how that can be, unless the control panel in the dash is bad. And I am guessing when I say that. The Nissan name for the control panel is AUTO AMPLIFIER that uses a micro processor.

Removing the radio whether it is the original Nissan radio or an aftermarket is the same process and not hard at all. Here is a link to a youtube video on how to do it.

dnichols5053

The pressure sensor was replaced when the mechanic had it... thats why I am leaning towards the interior sensor that I just found out about. I have replaced everything else. Today on the way home the temp in the RPM Gage said 50 F and the console AMB said 19 F. and the air blows but not cold.

DennisMik

iTrader: (2)

What I am coming to realize is that you are thinking that the AMBient (meaning outside) temperature sensor is the problem. While I don't know if that is correct, the sensor that is behind the radio is not the ambient sensor. The ambient sensor is located in the front bumper on the right side down by the fog light. If the instrument cluster shows one temperature and the a/c controls show another, you have to look at which one is correct. If both readouts are wrong by a large amount, then the sensor is messed up. If one of them is correct then the sensor is ok and the unit with the wrong readout is messed up.

I am going to assume that the actual temperature was 50º so the a/c control unit readout was messed up. What I don't understand is how the self diagnostic test could have run ok. But then, the self diagnostic test has no idea what any of the temperature sensors should show. The self diagnostic just shows you whatever reading the sensor is sending. It is up to you to determine if that is correct or not. Unless the sensor is totally dead, the diagnostic will not generate an error for this.

FYI, if you are using the a/c by pressing the AUTO button, the compressor will run all the time regardless of whether the vents are blowing warm air or cold air. If you use the ECON button, the compressor will only run if the setting in the dash is set to be lower than the amb temperature and cold air will blow constantly.

Turbobink

iTrader: (2)

Perhaps starting from scratch might be a good approach.

Meaning, let's establish the operational condition of your A/C system and work from there.

Step 1: Establish, through the use of appropriate manifold gauges, that your system is properly/adequately charged ... both high and low side pressures are within normal ranges.

Verify this and we can move to step 2.

User1

Clutch is toast. Jumper it with the engine off. If not engaging every single time, junk it.

dnichols5053

When you jump the relay it turns on.(the clutch) Dealer parts guy say it might be related to the two sun sensors on top of the dash

Turbobink

iTrader: (2)

The sun load sensor(s) have nothing to do with compressor activation and deactivation.

The sun load load sensors control fan/blower speed.

dnichols5053

I think I will junk it. Going back to German cars.

User1

Good call. S550.

dnichols5053

oh...by the way ol'wise one. why would a car need TWO sun sensors. Because it is related to the temp. control system.

Turbobink

iTrader: (2)

You need to do a little more research before you attempt to espouse your knowledge of an automotive system you, by your own admission (see post # 1), know nothing about. Even more so in a situation wherein you feel compelled to critique the knowledge and experience of others.

... and by-the-way ... according to the FSM (which is an abbreviation for Factory Service Manual) for your car (2000-2003 Nissan Maxima), that vehicle includes a single (as in one) sun load sensor.

This might actually be a good idea for you:

The Wizard

iTrader: (43)

If you think German cars are more reliable or easier to work on than Japanese cars, you're in for a real shocker. Best of luck!

dnichols5053

The (EATC) electronic automatic temperature control system uses the sun load and in-cabin temperature sensor inputs to adjust blower speed and improve passenger comfort. The sun load sensor contains a photo diode that's sensitive to sun light. Resistance in the sensor increases as sun load increases. If the sensor is covered with a dash cover or a window sticker, the control module will receive inaccurate information and make incorrect adjustments.

EATC systems allow operators to set a desired temperature and the system maintains that level of comfort. If the sun load sensor fails, a fault code will set, and the program will enter a default value and try to achieve the desired temperature setting.