Mndsm
Mndsm MegaDork
9/3/18 3:38 p.m.

Subject is a 2014 Nissan Versa note- also known as....the car that had a/c. Notice I said...had. Yesterday stopped at 711 to get a soda and some gas before going to run errands. A/c made a bit of a weird noise prior, didnt think much of it. Thought a lot berkeleying more of it when it did not do a/c things upon startup. Quick symptomatic diagnosis indicates the compressor is doing compressor things- car driven at speed will cold air through the vents when the a/c is clicked on. At one point after stopping for whatever, and restarting the car- the blower worked again! For about 45 seconds. So- we have a blower issue somewhere. Common diagnosis includes resistor (my albeit limited understanding of electrical says no- simply because the motor worked once after death- a blown resistor is a blown resistor. ) or.....the blower motor.  Given that it sounded like it sucked in some leaves prior to death, it lives outside, has been outside through two hurricanes and runs the ac every day except maybe winter, I bet it hoovered up some of central Floridas finest foliage. Disassembly is NOT the 25 hours of I'm not removing a berkeleying dashboard I originally envisioned. It is also NOT the take out the glovebox with a Philips head easiness that Nissan forums claimed it was. It's actually somewhere in between. NICO forums (shout shoutout to those guys) has the factory service manual. After I threw my phone in the garbage, almost threw the laptop in the garbage, and wanted to throw the cat in the garbage (he was knocking E36 M3 off the walls while this was going on) I managed to get the pdf to pull. And the winner is? I should be able to do this job. I need remove the lower kick panel and the gas pedal. Swmbo was not pleased when I said take off the gas pedal- if it's anything like the mini- it's a plug and a couple bolts, at least the FSM said so. Take those two things out, r&r blower, maybe clean out foliage from HVAC, easy peasy. I'm going to order the motor from partsgeek- it's the cheapest by 50 bucks. Autoboyvance claims to have one for 80$ in stock. Orly lolnoped me. I didn't check rockauto- maybe I will. Nissan wants 170 berkeleyin dollars for a little electric motor with a plastic fan on it. I'm half tempted to throw the castle setup out of my rc truck into it, but I'm not entirely sure an hvac fan needs to move at 100k rpm. 

 

TLDR- ac doesnt blow. Is cold. Interweb tells me either motor is fooked or resistor is fooked. Fan coming on once after death tells me motor is fooked. I'm not an expert, I'm not sure how else to narrow down and dx the thing before o order a motor. Anything else I can check?

EastCoastMojo
EastCoastMojo Mod Squad
9/3/18 3:54 p.m.

If it blows air on the high speed setting only, it's the resistor. Did you check the fuses? Quick online search seemed to indicate there is one for a/c and one for the fan.

Mndsm
Mndsm MegaDork
9/3/18 4:18 p.m.

In reply to EastCoastMojo :

Checked blower fuses. Both are clean. Ac compressor kicks in when I turn it on, you can hear it, just no blow job. It worked at all speeds, once. Works at no speeds since then. 

noddaz
noddaz SuperDork
9/3/18 7:53 p.m.

So, take the motor out for practice and hook a couple of jumper wires to it to see if it works.

If it is easy to get out.  BTW, if I remember correctly, some later Nissans have the blower resistor built into the motor.

noddaz

Vigo
Vigo UltimaDork
9/4/18 9:43 a.m.

Lots of interesting things here..First off if the blower resistor was bad the motor would still work on the high speed setting. If it doesn't run at all you have either a power or ground issue at the motor. Looking at the ground path, the AC switch splices into the same ground as the motor, and the ac switch works so from the blower switch to its ground point works. The motor has 4 possible ground paths TO the blower switch and if the blower doesn't work on any speed setting the chances of all 4 being broke is very slim, so those factors together make a ground issue pretty unlikely. You also have two fuses in parallel to power the motor but if one had a problem and the other didn't it would still work, and your intermittent symptom suggest they aren't both blown or you'd have no action ever at all, so you probably have two good fuses. Then you've got the blower relay. Looking at the diagram, if the blower relay wasn't engaging, you  ALSO wouldn't get  the little light on your ac button lighting up. 

So basically, if your ac button lights up i would say you need to replace the blower motor and if not you need to find that relay. cheeky Can you tell i like these diagrams? I'm also teaching an electrical class right now but i dont think it will get as far as this type of diagram. Sadly.

Our Preferred Partners
i5f453pNfIyywaIztzuI85G3auptofDk1S0oabCxTu4jgshDcMeD54bpuydCpYpU