Recirculation and AC problem

[Phifross]

Also I got 1.8ohm....

Again this morning through the test I was checking the different temperature.
At the beginning the three sensors had the same temperature, it fine.

When the AC on for a while the evap sensor temp was showing something around 0 to 1 degrees Celsius.
Is it OK?

The two other sensor were ok, no strange behavior from them.

[Phifross]

Ah but funny thing....

I reconnect everything the three sensors were showing the correct temperature but when I did again the self test, normally on step 4.1 the AC should crank on, and before I checked the ohm it was...
But now it's not cranking on....

But the location where the air blowing is OK, the power too.... but the AC not cranking on....

[Phifross]

At least now I'm sure if theAC is not cranking on, it's not because of any temperature sensor because all of them were OK, I checked three times while the AC was not cranking on.

Maybe it's the head unit?

[VStar650CL]

Could be a bad head unit, yes. That Intake Sensor signal might be normal, it's measuring the temperature of the evap (the part of the A/C which makes the air get cold). With the A/C active, it should go down near 0C. However, it shouldn't freeze up. If the evap turns into a block of ice then the air can't get through and you lose A/C until you shut the system down and let the ice melt. The usual cause of that (if that's what is happening) is a bad TXV Valve.

[Phifross]

For the evap temp, when it reach -0.5C the AC turned off, also it's working fine.
I have never seen ice block there.

Ok, will go to change the head unit...
I guess we can find only second hand....
any recommendations on where to buy?

I have seen some on Ebay....

[VStar650CL]

EBay is fine, just make sure the part number matches the original. There's usually a p/n tag on the unit someplace. If not, let a Nissan parts department get you the right p/n from the VIN. They can also print you out a "supersession chain" that shows all the p/n's which will be a right fit.

[Phifross]

You are really great and patient, thanks a lot, your advices were really helpful!!!

Last question even the head unit is looking the same, I mean same buttons... it can be different?

I have seen on Ebay same head unit but they had different number.
One had 27500 4W900
3F290 34700

Another had
27500 6W001
5C561 34700

Does it mean it would be better to check mine first before to buy it?

I don't trust much Nissan parts even with my VIN....
It gave me even another number code...

[VStar650CL]

You can't go by the way it looks, the firmware and even the connector layout can be very different if the part comes from a different model-year. Don't take chances with that. If there's no p/n tag on your existing head, call a dealer with your VIN and let them look it up for you.

[VStar650CL]

PS - The 27500 numbers are the Nissan p/n. The others are manufacturer or interchange numbers.

[Phifross]

Ok I will check directly on the car because when I put my VIN on the Nissan.oemparts site it gave for my car the head unit number (27500-5W911) but this is not the one I have, the buttons are really different.

Also better to check directly on the car.

Again thanks so much!!!