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Discussion Starter #1
Hello,

i am hoping you guys can give me ideas of things to check out.

Battery died on me after 16 months, i usually let car sit anywhere from 1 to 2 weeks in my garage. I replaced battery and drove the car 3 days in a row and it was fine. It sat for 3 days and was dead. I suspected the FSU and replaced it along w/ another new battery. Now i hear a grinding or humming sound behind the climate control after i turn off the car. I sat in the car for 30min to see if it would stop and go into "sleep" mode. When i pull the fuse for climate control the sound stops. Any ideas? I have been using the car everyday for about a month now and usually pull the fuse at over night and leave it in during the day time.

TIA

jason
 

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The automatic climate control has a very small fan inside to pull air in the small grille to sample the cabin air temp. I thin the grille is on the lower left side of the climate controller. 1 grille is false, the other is open.

As I recall this fan should run once you open the door and until the car goes to sleep.

You need to be careful as if you just turn the car off and do not open and close at least the drivers door the system electronics may not go to sleep correctly??

Best bet is to put a Ampmeter on the battery cable and take some spot measurements to make sure the system electronics are properly shutting down.

You may have a issue with something other than the climate control fan??
 

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I vote for the sampler fan too, and I suspect yours need a good lubrication considering the age of the car.
 

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I hear a slight clattering of sorts from this area and have been wondering what it is as well.

Best way to get in there and lube the fan? Remove the nav unit?
 

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Discussion Starter #6
ok, i will check out the fan, but any ideas about it always making noise, even up to 2 hours after i shut off car?
 

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I knocked out the sample fan cleaning this evening and took some pics to help others. I also installed Diny's nav unit knobs, they look awesome, see pics below.

I tried going the cup holders route and only succeeded in putting some small scratches on the leather, there is vertical metal piece in there that doesn't want to budge. I ended up taking out the Nav unit instead.

TOOLS:
Phillips screwdriver, preferably magnetic tip
Compressed air
Cleaner - I used an alcohol wipe
Lube - I used Miltec1, an advanced gun lube, lithium based would probably be fine

INSTRUCTIONS
1. Remove nav unit bezel
Remove the small metal/wood trim piece around the tire pressure sensor, this gives you some leverage to pop out the nav bezel. Be patient and use care on the nav bezel, it's all plastic tabs so work your way around slowly. The picture below shows the popped out tire sensor trim piece.



2. Remove Nav Unit
There are four phillips screws (marked GREEN below) you'll need to remove then the nav unit will pull straight out. There are screws in the upper left and upper right corners, the remaining two are in the bottom left quadrant. It's easier to access the bottom screws if you tilt the face of the nav unit out as in my second pic below.

It looks like there should be two more screws in the lower right quadrant (marked YELLOW), there aren't. When you remove the unit you'll see that there aren't screw taps there. Don't remove the four small screws (marked RED), these are for the face of the nav unit.





3. Disconnect nav wiring
Remove the two connectors from the back of the nav unit and set it aside. There is a third connector in the wiring loom on my car (marked YELLOW) it is NOT USED. Not sure what it's for, maybe some cars got a Weapons Van button or something.



4. Remove and disconnect HVAC unit
Use leverage from above and pushed the HVAC unit out towards me. There are two metal clips, one each side, that retain the unit. It doesn't take much pressure. Then disconnect the four connectors from the back of the HVAC unit, I found the three wire plug on the right in the picture to be a bit stubborn, put pressure on the tabs on its outside. Remove the HVAC unit from the car to a well lit work space.



5. Open (split) the HVAC unit
To open up the HVAC unit you need to pop a set of plastic tabs (marked GREEN) on both the top and bottom of the housing. Once these tabs are loose the unit will open up.

The metal tabs (marked RED) should stay in place, they keep the circuit board for the buttons in place against the face of the unit. If they pop out, no biggie, but you'll want them popped back in before reassembly.



6. Pull the circuit board
The circuit board with pull directly out. Note the pins in the middle right of the pic, these will need to be mated to the front of the face when you reassemble.



7. Clean and lube
The first pic shows the dust and grunge accumulated on my fan and the entry port from the front of the nav unit. The fan can be pulled straight upward, it's only held on by magnetism and its small shaft. I used compressed air and an alcohol cleaning wipe to clean the fan, the entry port, and the fan housing (marked in YELLOW). I used a very small amount molecular gun lube on the shaft of the fan (marked GREEN).





8. Reassemble
This is pretty much the reverse of the above. Take care putting the two halves of the HVAC unit back together, the tabs are a bit tricky. The image below shows a tab (marked GREEN) that needa to pop-in, another tab that needs to slide OVER the recess against it (marked YELLOW) and the metal tabs (marked RED) that should all be in place before snapping the halves back together. It's obvious if you don't have it right; you'll see gaps or ridges where the pieces aren't flush when viewed from the back.

 

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Sorry to bring up an old(er) thread, but I am now having this issue and would like to understand; this process very likely reduces the sound that the fan makes, but does it stop it from running when the car is off? That's my main concern, the fan is going with really no need . . . Then of course over time, I suspect I will have a dead battery. Sorry if I'm missing something, but while the fan noise is somewhat annoying, the battery issue is a bigger concern for me, thanks! KH
 

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The fan is designed to run for quite some time after the car is shut off.
 
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