Problems with the cabin blower seem to be frequent and I am amongst those who had a screeching blower motor. If the blower isn't repaired or replaced it will ultimately take the blower resistor out on a MCC unit or the power stage on an ECC unit. The blower resistors and the power stage units are nearly as expensive as the blower so preventative maintenance can save some money in the long run.
To replace the blower you first need to remove the lower dash panel on the passenger's side of the car. It is held in place with three T-25 Torx head screws. Once the lower dash panel is removed you will be greeted with the knee bolster which has an SRS sticker on it.
Fear not, the knee bolster has nothing to do with the SRS and you can remove it without worry of setting of an air bag. The knee bolster is held on with three nuts. Use a deep 13mm socket and an extension to remove the nuts. You can fight it out now or you can wait until after you remove the glove box.
The next step is to remove the glove box. You first need to release the retainer arms with a small screwdriver. Next to the glove box door side of each of the arms there is a small hole. Slide the screwdriver into the hole and it will release the arm.
After the arms are released you need to remove the 6 T-25 Torx head screws that hold the glove box into the dashboard. Once the screws are removed pull the glove box forward and then press it down on the top so that it can clear the latch brace.
If you have not yet removed the knee bolster that is the next step. It comes off easier with the glove box out since you can smack it from behind to release it from the studs.
At this point you can see the blower and its four T-25 Torx screws that hold it in place.
There are two screws on the left (high and low) and two screws on the right that are much nearer the center. Before removing the screws you need to remove some of the wiring harness that is anchored on the blower housing. Near the bottom there is a connector that is held in place by the blower itself. That connector needs to be removed from the blower but it doesn't need to be disconnected. There are a couple of release tabs that need to be pulled back to get it off. I am pointing to it in this picture.
The wiring harness that mates into the blower from above also needs to be released. It simply pulls out away from the blower. And finally the power connector for the blower itself need to be removed. On the ECC it is the connector with the blue wire and the red wire.
After removing the 4 mounting screws the blower slides out for removal. It will take a bit of playing with it to get around the wring harness but once clear it comes right out.
If you are replacing the entire assembly the replacement would simply slide back in place and - as they say - installation is the opposite of the removal. In my case I tore the blower apart and lubricated it hoping to at least postpone the inevitable replacement for a while.
Lee, any pointers on taking the blower apart for lubing?
You need to remove the blower motor from the mounting. It is held on with a T-15 or T-20 (off the top of my head I can't remember) Torx through a rubber grommet. After you remove the screw you need to remove the grommet and then remove the power connector. At that point the blower motor will slide out of the mounting. The rear bearing is a piece of cake, just oil it. The front bearing is a bearcat unless you remove the squirrel cage blower. I just drowned the front bearing with WD-40 and left the squirrel cage on mopping up the excess oil when I was done. I plugged the fan back in and ran it forward and backwards a few times by flipping the polarity on the power connector until the oil made its way into the bearing. I had to re-oil it a couple of times along the way and repeat the process. So far it is working but we shall see how it does in the long run.
Just wondering if WD40 is the best oil for this? I have heard differing opinions. I know that places like Harbor Freight actually sell a electrical motor lube which I think would last longer than the WD40. Anyway, I suppose I would just use what I had sitting around.
'98 S70 T5 Emrld Grn Met/Beige Tons of Upgrades Mobil-1 '04 V70 2.5T Red/Taupe Some Upgrades Mobil-1 94 850 Sedan NA Drk Blue/Tan '00 V40 Purple/Grey Mobil-1
Good write up Lee. This is becoming a more common problem as these cars age. I just did this service on my old Mercedes 300D (basically the same setup and fan). These motors will go a long time if lubed every few years.
It is easy to remove the fan from the motor assembly. Mark the top of the fan and motor shaft with paint (it is a balanced assembly). Place the bottom of the fan on a couple blocks of wood on each side. With a drift, lightly tap the shaft through the fan assy.
Lube the front bearing and blow all the dust off the windings. Assemble the fan back onto the shaft noting the previous paint marks.
Models that have the MCC... The blower resistor can be repaired for only a few bucks if you have soldering equipment. When the bearings on the fan lose there lubrication, the increased resistance in the windings and wiring will blow the "thermal fuse" on the MCC "Blower Resistor". A replacement resistor can be found at any electronics shop for a about $2 to $3. A little silver solder and you are back in business.
They are not thermally protected to the best of my knowledge. It might be a brush hanging up or a bad contact on the spade lugs that actually plug into the motor. You need to pull the blower to get to either one of those. While it is out it sure wouldn't hurt to lubricate it.