FYI Fan Amplifier repairable...
 

I searched and found those with auto climate control sometimes replaced the fan amplifier for around $90. In my case, the fan would not work. The display, AC and heat worked, the fan simply wouldn't blow. I removed the fan amp (below glove box area, clear/white plastic cover) and re-soldered all large connections. About 5 in total. This fixed my issue.

This same thing occurs with some older G20's, so i was prepared. This is mostly for future search purposes.

Glad to hear that helped you and hope it helps others. The mosfet power amp (little chip in the fan amp) keeps blowing in mine (2nd one). I've got what I hope is a fix on order. After I try it (should get here Thurs), I'll post results.

Usually this is a sign that it's time to change the fan motor (drawing too much current).

I may have spoken too soon. It worked last night and this morning, but no longer. It never stops working whle driving, only once the car is shut off, then restarted. I also changed my blower motor last night with a used unit.

I noticed that both my original blower and the new/used one had a little "tension" when rotaing the fan. It spins fine, it just doesn't keep spinning long.

I'll check the solder again, and may just have to spring for a new amplifier. I don't want to burn out a new one though if another issue is at fault. Please keep this thread alive with updates.

Well, it looks like I will be ordering a new fan amplifier. I'm also going to replace the used blower motor I got yesterday. Thankfully, I purchased the used blower motor from a wrecking yard on eBay who has a lifetime warranty on the part. not to mention it was only 50.00 with shipping.

The issue is both the new/used and my original blower motor bearings seem to be shot. I can spin the fan no more than 1-2 revolutions. I searched and found that bad bearings can lead to excessive draw of current through the fan amplifier.

Again, I'm only mentioning this for future search purposes. The info found here is invaluable, and I'm happy to contribute.

I'd agree with you, but some folks that know a bit more about electronics than I do are telling me that's not the case in my situation.
I did check amperage draw by bypassing the fan amp, and it's pulling less than 10 A, which should be well within the fan amp's capabilities. I also pulled the blower motor and checked the bearings - it spins fine, so I'm pretty sure it's not the motor. Thanks for the help though.
The replacement mosfet that I'm getting is good up to 80A continuous, so if this works, I think I'll probably blow a fuse or other some other component before the mosfet if my problem is due to current consumption.

Curious. When you checked the bearings, spinning the fan, did it spin freely for more than 1-2 revolutions? I'm trying to determine what is acceptable here. Also, if you believe your fan is good, what do you think may be the cause in your case for blowing the fan amp? Good info here, keep it up!

When I pulled the fan (right after my 2nd fan amp blew), it freely rotated more than 1-2 revolutions, though I can't tell you exactly how many because I wasn't really counting. This is actually my 2nd fan - I bought it used and installed it after my first fan amp blew (the first fan did have rough bearings). I think it might be either just bad luck with the 2nd amp, or maybe I have an intermittent short somewhere, but haven't been able to find anything yet.
Both times, the fan amp has failed 'on' (the fan was operating at less than full speed, and then went to full speed and stayed there, no matter what fan speed was selected or if I turned the climate control off).
There's a more than a few posts on the web that mention this same problem with the same mosfet, whether it's a Acura, Nissan, or whatever, and questions about a replacement. Unfortunately, it's a 'custom' part, so there's no spec sheet available, and it's not available at your local Radio Shack. I'll let you guys know what happens ....

My fan squeaks when it blows. Once I'm in there is there a way for me to find out where to lubricate it?

The fan uses sealed sleeve bearings, so I'd say no. If you figure out how, let us all know - these fan problems get expensive!

This may be of interest. http://www.trademotion.com/partlocat...=4&catalogid=2

The fan amp listed here as "module" is 50.69. In addition, looking at the illustration, they list the motor as a separate assy from the fan. I need to look into this further though...

A blower motor for $8? Is that right? If that's true, that'd be sweet!:greenboun
The stealership wanted $250, and most junkyards don't sell them for under $50. Let us know what you find out...

Fan Amp Fixed!
 

O.k. I was going to post this earlier, but I wanted to make sure that the mosfet would hold up for a while before releasing this information.

First a word of warning:
I don't claim to be an electronics expert. I won't be held responsible for any damage from misdiagnosis, improper repair, or any other reason. All I can say is that this fix worked for me. Also, anyone that doesn't know what a resistor, thermal fuse, or soldering gun is probably shouldn't attempt to fix their fan amp - just get another one.:ben:

Now the good stuff - the original Mosfet is a NEC 2SK2500 (I originally misread the p/n in another post). However, you can't buy it, or get an info on it because it's a 'custom part'. I did find one that would work - here's the datasheet:

http://www.fuji-electric.biz/Semi/Da...ET/2sk2690.PDF

I bought mine from Allied Electronics for $6.70 - alot cheaper than the stealer, huh? :lolrun:

http://www.alliedelec.com/Search/Pro...C=2SK2690%2D01

:werd:

Awesome. I think the 8.00 motor is a no go. I looked at my old one, I don't see it being servicable from the fan. I'll look into this new mosfet, thanks for the post.

2002 SE Fan Doesn't work in 1,2,3 but works in 4
 

Hi, Sorry about replying in this old thread. But I have a problem with my fan system. The fan doesn't work in 1 2 or 3 but does blow in 4. I already figure out it's not a fan control (manual control) problem, what control be the problem? Would changing out the fan motor fix this problem? Any input would be welcome. Thanks!

yycools - If I read your post correctly it sounds like you have the manual climate control. If that is the case it sounds like your blow motor resistor is shot. I replaced it in my mother in laws 2000 Maxima a couple of years ago. I think the part was about $40 and it was really east to replace. I know there are some threads here in the 5th gen forum regarding this issue.

Thanks! I will try to find it.

Has anyone used Zoner's suggested MOSFET replacement for the Fan Amp and if so did your experience good long-term reliability with the FUJI 2SK2690 replacement.



Here's Zoner's original posting:

Saw one of your old posts below about the Mosfet 2sk2690 replacement & wondered if it had been a longterm reliable replacement, Thank you for your input.

Now the good stuff - the original Mosfet is a NEC 2SK2500 (I originally misread the p/n in another post). However, you can't buy it, or get an info on it because it's a 'custom part'. I did find one that would work - here's the datasheet:

http://www.fuji-electric.biz/Semi/Da...ET/2sk2690.PDF

I bought mine from Allied Electronics for $6.70 - alot cheaper than the stealer, huh? :lolrun:

http://www.alliedelec.com/Search/Pro...C=2SK2690%2D01

I'm still running the same chip I put in back in '06. One small point I forgot to mention - when you 're installing the chip, bend the legs 90 degrees before putting it in. Install the chip in the casing first, make sure it makes good contact with the casing, then put the board in and solder the legs. It's important to install it this way, or else the new chip will not make contact with the casing (it's a heat sink) and overheat when you use it.

FYI...diagnose available for ACC
 

For those of you who have the ACC there is a self-diagnostic feature in the ACC unit.

If you have the FSM it is in the heater & air conditioner section under "How to Perform Trouble Diagnoses for Quick and Accurate Repair." In my FSM it is on page HA-47.

This helped me easily diagnose my problem as the auto amplifier. When I pulled it I found it was fried (visible burns on the board). I verified the blower motor to be working by applying voltage direct from the battery and it turned fine.

Someone in this thread posted earlier about concerns with the blower motor bearing due to only a couple rotations by hand turning. I'm not sure this is not a good indicator because my motor made three revolutions by hand, but turned fine with the voltage from the battery. I suppose we will see when I get a new auto amplifier installed. If the new one burns out quick then root cause is probably my blower motor.

What's a good amperage for the fan?
 

I just had my blower motor stop working on my 2000 Max with the auto air; luckily we're still getting 85F days here so it hasn't been bad.

The immediate cause was activation of the thermal fuse inside the blower motor amplifier, and it's back to working with a replacement blower motor amplifier. Thanks to this link for good details: http://forums.nicoclub.com/how-to-fi...r-t433421.html

However, I put a trusted amp meter inline with the battery and powered the motor directly and measured 15.0A at 11.7V (176W). There's no junk in the motor and it sounds fine. Can anyone tell me whether 15A is a reasonable pull for the motor directly connected to the battery?

Given that the blower motor circuit appears to have two 15A fuses in parallel (resulting in a max of about 30A), I would think I'm well within limits, but it would be nice to know for sure before I take this amplifier out too.

Also, I haven't really wanted a new car, but actually holding the part in my hand that is pre-heating the air to the AC system while the fan is running at mid-speed in the heat of summer is kind of painful... presumably modern vehicles use an even more expensive but efficient PWM or brushless motor control?

Thanks!
Peter

As an update, I've been running the AC on and off for a week with the new amplifier in place with no problems yet. I've also replaced the components in my old amplifier and will hang on to that for a while in case there's a problem.

Just as an added FYI...in the case where you clean your internal cabin air filters make sure they are completely dry and at ambient temperature prior to re-installing.

The blower motor amplifier is directly below the filters. I have a strong suspicion this is how I shorted/lost my amplifier as it went out a short time after I had cleaned my cabin air filters.