Post by
Infiniti4Me »
https://forums.nicoclub.com/infiniti4me-u261394.html
Wed Feb 10, 2016 2:26 pm
Hi gang! New member here and I want to really thank you guys for this thread, and more importantly, for keeping it alive and updated for 7 years!! Truly a Legacy thread...
Skibane, big thanks to you, especially!
I just bought a 2000 QX4 for a very low price with the explicit understanding that I would have to put some money and work into it to bring it up to a reliable daily driver. I realize its 16 years old, so it won't ever be perfect, but even carfax said it was a recommended buy at that price! The HVAC isn't a "do or die driving" problem, but, it seems like one I might be able to do on my own. My first few searches lead me to this forum and thread, and I think my problem fits into this mold:
Everything HVAC _looks_ like its working (lights, door noises, speed adjustment, temp adjustment, etc), but I never get any actual air. The only time I _do_ get air is on the highest fan setting while traveling at higher speeds and I've read that the air coming in isn't actually fan/blower related, its just from having the vent doors wide open. There is no intermittent "on sometimes, off more often" ... "comes on if i hit things" ... no "stuck on high at all times." None of that. Just no air.
I looked at the fuses and one of the Blower fuses was blown (J/B, #1, I got all excited, but sadly, that wasn't the primary cause) and the second Blower fuse was a 20A, instead of the 15A it should be. I pulled out the 20A and put in the right one, but, again, no such luck. I'm hoping the 20A didn't eff things up beyond repair, as I've been reading the Infiniti factory service manual, and they say never to use a fuse with a higher rating.
At any rate, seeing as I'm very budget-minded, I figured I'd jump into the fix detailed here, but I want to make sure I'm doing everything in the correct order. I checked the driver-side fuses, replaced 1 blown/"open" 15A fuse in the fuse box J/B, position 1, and replaced an in-place 20A fuse with the correct 15A in J/B position 2. I ran through the self-diagnostic for the HVAC, with mode 2 always coming back "25" (even in direct sun). I've read that sometimes the blower fan can be jammed up with dust and other nastiness, but mine was totally clean. I spun the blower fan by hand a few times and it spins around with ease. I took a look at the fan control amp to see if there were any obvious signs of it being broken, but I couldn't tell, so I put everything back in with the hopes that just a little re-wiggling doing the trick, but no such luck.
(A couple other things are problematic, but I think because of their own, separate issues. I'm mentioning them only because they are in the general vicinity of the HVAC: Along with the HVAC never blowing air, the Radio illumination goes on and off intermittently. Everything audio works well enough-- it doesn't fade out occasionally and the radio/audio always works, whether the radio lights are on or off. Also, the AIR BAG light on my main dash constantly blinks. Could be any number of things, but I mention it because of possible HVAC interaction. Maybe its blinking because someone previously tried to fix the blower and somehow screwed it up?)
Have I missed anything? I've haven't spent much time with a digital multimeter, tho I do own one. I'm a relatively quick learner, so I figured I'd start off with a quick youtube lesson on how to use my DMM before delving too deep into the project. I've also read that replacing the blower motor and fan control amp at the same time is recommended. Should I just bite the bullet and spend the, what $400?, to buy both parts and self-install, and hope it doesn't burn out again too quickly?
Anyway, sorry for this monster wall of text, but I figured I'd be as thorough as possible. Thanks again for all your help and effort, Skibane and crew!