Did a search and learned a lot but didn't find exactly what I'm looking for, although I now know exactly how to take apart the right side and center of the dash to access the blower motor (if that is the cause of my issue).

The other day I needed to just get voltage for the windows so I hit the start button without pushing the brake pedal. Don't know if this had anything to do with anything but I mention it. When next I started the car, blower fan did not turn on. All HVAC lights and controls and displays appear normal.

Turned car off, and restarted it, and same thing. No fan. Turned it off a second time, restarted it and everything was working fine. (5 or 6 years ago I had an issue with my cruise control not working a few times when I started the car. Turning car off and then on fixed it the 2 times it happened, and it has never happened again, but I digress.).

I've started the car many times over the past few days and everything seemed to be working fine.
Today, I start the car up and no fan. A few consecutive stops and starts have not solved the issue.

My questions:

After I finish writing this, I'm going to check the fuses to see if anything is blown. If all look good, what would be the typical order of things to check next? Does this sound like something that typically goes wrong? Should I check a resistor next or amplifier unit (control unit)? I'm just not sure what is the proper order of things to check in accordance with what typically goes wrong.

Would something like this be covered in the shop manual? I have a digital multimeter and have a barebones knowledge of how to use it. I can check voltages, resistance, and continuity, but when people mention things like checking for signal, I have no idea what they are talking about.
Any guidance would be appreciated!

Thanks in advance.

Since it's an SL, I assume it has Auto A/C. The Auto's on the gen2 use a funky 2-speed VBC (blower resistor) that controls both the high and low sides of the blower supply, so the only good way to find out if the blower or VBC is at fault is to catch it in the act and then see if a test light across the blower motor connector lights up. If so, the motor is bad, if not, the VBC is bad. My suspicion would be a bad motor, since it's unusual (although not unheard of) for both circuits in the VBC to fail. Usually a bad VBC results in weird complaints like the blower "going away" as the temperature is turned up, because only one circuit is fried. One other note, there's a Blower Relay on the back of the fusebox, but you don't need to access it to check it. The two parallel blower fuses are downstream from the relay, so if the fuses have power with the key on, the relay is good. Use a bulb-type test lamp and not a voltmeter, a meter won't tell you if the relay contacts are crappy, a dim test lamp will.

Thanks VSTAR650CL for the reply!!!

I checked both 15A blower fuses, (I was surprised that they are separated from each other so far in the block) and they looked good. I tested continuity just in case, while they were out of the fuse block.

Yes, the SL has Auto A/C. I've not had the blower "going away" as you mention.

To test the blower relay with a test light... just want to make sure I'm doing things correctly...
With a test light (12volt bulb and leads) if I have the engine running, do I put the light's probes across the two openings in the back of the first fuse, and then the other? Just want to make sure that testing from the back of each fuse is correct. Does it make any difference what fan speed is selected on the dash?

Also, Is the resistor pack tucked up above and to the side of the brake and gas pedal, or is it near the blower? Or, is one of the spots I mentioned where the "amplifier" is located? Yes, I don't have a lot of knowledge, but I do have enough to be dangerous

Thanks again

To check fuses with a test lamp (which is the only right way to check them), you put one lead on ground, then the other lead to each side of the fuse in turn. There are three possible results:
Both sides light up - fuse is good and has power
One side lights up - Fuse has power but is blown
Neither side lights up - Fuse has no power

To check the blower with a test lamp, take the connector loose and check across the pins. You're basically substituting the lamp for the blower motor. If the lamp lights then the blower motor has power but isn't running, which means the brushes in the motor are dying. If the lamp doesn't light (or lights dimly) then it means the VBC isn't sending it proper power or ground, so the VBC is bad. If the VBC shows bad, replace the blower too. Dead VBC's almost always come from dying motors that draw too much current.

You can see the locations of everything here on HAC-8:
https://www.nicoclub.com/service-manual ... %2Fhac.pdf
The pertinent view is of the driver's side of the HVAC, the VBC is above and behind the gas pedal.

Slightly different tack here...

Just for the heck of it, while the engine was running and the fan was set to high (but obviously not spinning), I decided to give the top of the dash a few raps with my palm. Nothing. Then I gave the dashboard a rap, on the curved panel just to the left of the glove box opening, and the fan started right up. It worked all the way home with no problem.

Once home, I turned the car off, and then restarted it without touching any of the HVAC controls. Upon engine start, the fan came back on, but as it was starting, I heard a faint tick, tick, tick, for about 2 seconds...until the sound of moving air drowned it out.

Can anything be gleaned from this? My uneducated guess is something to do with the blower armature or brushes, as if the brushes were stuck on a part of the armature that was dirty, or dead, or maybe the brushes themselves are pretty well worn out.

I guess it could also be a loose connector, but I wouldn't know until I take the center and right side of the dash apart to get into the blower area.

Don't know if this is possible with this system, but with my old VW Rabbits, I used to get leaves and twigs that would find their way into the blower fan, and you'd get a high pitched whine (imagine baseball cards in bicycle spokes, but on turbo) until you reached into the fan which was situated just below the cowl vents, and removed the leaves and twigs. Can stuff find its way into the blower on the Rogue and lock up the fan?

Your thoughts?

Also, if you feel it's most likely the blower, are any of the aftermarket blowers any good, or is this a time to definitely get an OEM one? Does anyone sell rebuilt OEM versions?

Thanks

It's almost certainly a bad blower. They're brush fans, and starting up when a whack is applied is a sign of bad brushes. It's definitely not the sort of behavior you get from a bad VBC. You might also have some debris in the blower cage or cavity causing your tick-tick-tick, and that won't help matters. Vacuum it out while the cavity is open when you change out the blower.

PS - If you do find a substantial amount of debris in there, change out the cabin filter and vacuum out that cavity too.

Any thoughts as to OEM versus aftermarket blowers for this vehicle?

RockAuto sells fans made by (in price order, low to high); GPD, SKP, UAC, TYC, Four Seasons, VDO, and Nissan OEM.
The first 4 range from $40 to $80, and the last 2 for $160 to $180.

And thanks again for all of the assistance. It is greatly appreciated!

Andy

For some reason, it won't let me edit my post above. Pulled out the motor. I followed an excellent video on YouTube put out by Online Police. The only issues I had were removing the connectors from the back of the HVAC display (yes there are push to release tabs), and which way to turn the blower motor to unlock it after the screw is removed. This video says clockwise, while others say counterclockwise. My 2015 SL with a VIN of 5N1A******** needed to go clockwise.

I tested continuity across the 2 electrical terminals on the blower motor, and the meter kept starting and stopping screeching, meaning that the brushes/armature are not making good contact. I definitely need a new blower motor.

I pulled out the cabin filter and it somewhat shredded in my hand. There was a small handful of leaves and twigs that came out too. Gotta order a new filter.

andygold wrote: ↑

Mon Aug 15, 2022 12:42 pm

I tested continuity across the 2 electrical terminals on the blower motor, and the meter kept starting and stopping screeching, meaning that the brushes/armature are not making good contact. I definitely need a new blower motor.

I pulled out the cabin filter and it somewhat shredded in my hand. There was a small handful of leaves and twigs that came out too. Gotta order a new filter.

Definitely break out the shop vac while it's removed. There's nothing more aggravating than doing a blower job twice because some idiot pine needle was lodged someplace in the inlet or cavity.

andygold wrote: ↑

Mon Aug 15, 2022 8:37 am

Any thoughts as to OEM versus aftermarket blowers for this vehicle?

RockAuto sells fans made by (in price order, low to high); GPD, SKP, UAC, TYC, Four Seasons, VDO, and Nissan OEM.
The first 4 range from $40 to $80, and the last 2 for $160 to $180.

And thanks again for all of the assistance. It is greatly appreciated!

IMHO the OE blowers are overpriced, the bearings and construction don't seem any better than most aftermarket units. My customers have had decent luck with both TYC and Four Seasons.

Thank you again! Much appreciated!

You're most welcome. Happy motoring!

I bought a blower motor and resistor as a package deal from ebay for $45. Working like a champ since I put them in back in November. I replaced both since the cost was low and the aggravation was slightly high. While there, I also vacuumed out the cabin air filter housing and changed the filter.

VStar650CL wrote: ↑

Mon Aug 15, 2022 2:33 pm

You're most welcome. Happy motoring!

Could I send you some funds via PayPal as a thank you for your assistance?

andygold wrote: ↑

Fri Aug 19, 2022 8:27 am

Could I send you some funds via PayPal as a thank you for your assistance?

Nah. Long story, but this is just "paying it forward" for me. Knowledge is power no matter what the subject is, so pass it along to the next person who needs it. It makes the world a better place, trust me on that.

Cool! and again thank you VStar650CL. I always do try to pay things forward!

To those who may be following this....

As a follow-up. I installed the fan and put everything back together today. Success!!! I think the new fan may have a higher pitch whine and may move a little less air but that is not something I can say with 100% certainty. It's hard to compare as I cant run them side by side.

The fan was marked Unimotor 75041. Unimotor is a Four Seasons company.

When comparing the 2 fans side by side, the new fan blade is much shorter than the old one. Probably almost an inch and a half difference in length. Both flange/motor areas are about the same size in diameter and height. The difference is that the OEM blade almost touched the motor housing. This one has a gap of about 3/4" between blade and motor housing. Also, the Unimotor blade is approximately 3/4" shorter on the open end compared to the OEM. So, basically, the Unimotor fan blade does not extend as deep into the fan housing cavity, nor does it extend as close to the mounting flange as the OEM fan blade.
Not sure if anyone cares, but if I can post the images of the two fans side by side, I will.

andygold wrote: ↑

Fri Aug 19, 2022 3:59 pm

When comparing the 2 fans side by side, the new fan blade is much shorter than the old one. Probably almost an inch and a half difference in length. Both flange/motor areas are about the same size in diameter and height. The difference is that the OEM blade almost touched the motor housing. This one has a gap of about 3/4" between blade and motor housing. Also, the Unimotor blade is approximately 3/4" shorter on the open end compared to the OEM. So, basically, the Unimotor fan blade does not extend as deep into the fan housing cavity, nor does it extend as close to the mounting flange as the OEM fan blade.

That difference in length will definitely compromise the amount of air the fan can move. The way a squirrel-cage blower operates, a vortex of air is sucked into the center of the cage and then flung outwards by the curved blades. The air direction is changed 90 degrees, the same principle employed by a turbocharger but at much lower RPM. When the cavity is a loose fit to the end of the cage, some of the air exiting the vanes will be recycled back into the vortex in a circular flow through the gap, reducing both the output pressure and the total amount of air the blower can move. I'd send it back, they may say it "fits" but it doesn't really.
https://en.wikipedia.org/wiki/Centrifugal_fan