- How Things Work / DIY Section - |
| Mercedes-Benz | Porsche | Motorcycles & Miscellanea | How Things Work (DIY) Section |
According to Webster's -
fickle (fik´el) adj.
[
ME fikel < OE ficol, tricky < base of befician, to deceive, akin to gefic, betrayal,
deceit: for IE base see FEY] changeable or unstable in affection, interest, loyalty, etc.; capricious -SYN
INCONSTANT
-SYN INCONSTANT
I had (note the past tense) a "fickle" AC fan. Several times I'd pressed the "auto" button on the AC controller, and got no response. As long as 10 minutes later, the fan would start in full blast mode. It didn't happen every time, but enough so I would notice.
The problem was the blower motor resistor/regulator. As its name implies, the regulator governs power. In this case, power to the fan. I try to avoid stating how hard a task is because "hard" is a relative term. Some may not know that it's a bad idea to have power running through an electrical device while attempting to change it. Others may know and go overboard; disconnecting the battery and having to reset the windows, sunroof, seats, radio, and everything else. Those that simply turn off the car before changing the part may say it's an easy project that takes about 15 minutes. When I changed my regulator, I turned off the car and left the keys out of the ignition.
The regulator resides under the glove box, next to the cabin filter. To get to the regulator, access panels have to be removed. The panels are accessible from the passenger side of the car. The first panel is on the transmission tunnel. It has to be removed to make room to remove the second panel.
The screw on the first panel looks like it can be removed with a Phillips screwdriver, but it can't. The screw has to be pulled back. That can be done by prying it back with a small flathead screwdriver, some needle nose pliers, or with an upholstery tool. After the screw has been pulled back, I then pull the entire panel toward the rear of the car. The next photo is a shot of the panel after it's been removed. You can see that it's a slip fit with the pin to the left holding it in place.
First panel |
First panel when removed |
With that out of the way, the main panel can be removed. It's held in place by three Phillips screws and a plastic guide in the rear. After removing the three screws, I pull the panel toward the rear of the car.
Second panel
With the panels out of the way, the housing cover has to be removed. The housing cover is held in place by two clips. The clip closest to the front of the car slides rearward, and the clip closest to the rear of the car slides toward the front. The electrical connection is removed next. Pinch the sides of the connection together, and pull it off. The cover can then be pulled down.
The red arrows point to the clips, the yellow arrow points to the regulator. |
The housing cover after it's been removed. |
With the cover removed, you can see the fan and the regulator.
The regulator is held in place with two Torx screws. Before removing the screws, I disconnected the wires on the regulator. The new regulator came with wires, but they were a slightly different length, so I preferred to use the existing factory wires.
The front of a new regulator. |
The back of a new regulator. |
With the wires unplugged, I unscrewed the Torx screws and removed the regulator.
The new regulator goes in as expected.
- Install the two Torx screws
- Plug in the wires
- Test the fan by putting the key in the ignition and turning the fan on.
- After confirming the fan works, removing the key and reinstalling the housing cover and panels.
This job took me 30 minutes. That includes taking photos. With my "double check everything process", I've been known to work slowly, so others may be done much sooner.
So what does it cost? My Behr regulator cost about $100, but I used a reputable parts supplier. A cheap Ebay knockoff that shorts out the car and burns down the garage may have a slightly higher total cost of ownership.
Home | Mercedes-Benz | Porsche | Motorcycles & Miscellanea | How Things Work (DIY) Section
© 2011 Marcus Blair Fitzhugh