Removal and installation of blower motor on 2004 Mazda 3?

Answer 1

The short answer for many is this may be more work than one will want to undertake at home. Although it is a fairly straightforward process, there are many opportunities for derailment that will require an expensive dealer correction. It is a lengthy process and you will need to dedicate a weekend for the repair.

Before you take out the blower, do the following first as blowers usually don't go out:

• First, check your relay. It is located in the engine space, outboard of the battery in the fuse compartment. There is a small cover you snap out and that will expose a group of relays and fuses. The one you are looking for is marked "HEATER" on the cover. It pops in and out easily. The simplest way to test it is to swap it with the "STARTER" relay that is in the same space. They are identical and after you swap them, if the car won't start then you need to replace the relay.
• Next check the fuses. In the same compartment as the relay there is a 40A fuse labeled "HEATER". Check it to make sure it is not burned out. Also, under the glove compartment there are another group of fuses and one of them is labeled "A/C" (20A). Check it as well.

OK, so if you have done the above and still have no working fan, you have two remaining possibilities: One is the blower motor and the other is the blower motor resistor. In my case the problem turned out to be with the fan portion of the blower as once I removed it I could tell that it had actually melted on the motor shaft! (more on that later) Perhaps someone else can add the procedure for resistor removal and replacement.

I should mention here that I am describing a blower motor removal procedure for a Left-Hand Drive Mazda 3, but interestingly enough, if you have a Right-Hand Drive Mazda 3, this description still works. Everything under the dash is a mirror image of the LHD model, it's just that the passenger side is on the other side of the car.

Anyway, here is the process to remove the blower:

1. Remove wire from negative battery terminal. If you don't know where that is or what that is, stop here and call your local qualified mechanic and schedule him to do the blower replacement. You are not qualified!
2. Next, on the passenger side, slide the seat all the way back. Begin dissassembly by removing the fake carbon fiber bezel that surrounds the clock/radio display. Pull from the center, then to the left- there's a hook on the right, so free all the friction clips before pulling to the left.
3. Next, you will need to remove the glove box. This is facilitated by pulling off the rubber door seal from the body where it meets the outer portion of the glove box unit. Y will also need to remove the passenger kick panel down by the carpet...the glove box is supposed to have no screws but mine had one under it on the right outer most corner.
4. Once removed, you need to drop down the fuse panel that is under the glove box. Two set screws allow it to pivot and then you need to unhook it from the pivot mounts so it lays flat on the floor. Mazda shop calls for it to be disconnected but there's an electrical start-up procedure that's a pain and you can avoid it by leaving it connected but unhooking it from its frame.
5. If you look inside the space left behind by the glove box removal, up high under the dash and towards the center, you will see the end of the Heater/AC control housing. Everything at this point is black plastic. On the end of it is a small wire harness plugged in. That is the Fresh Air/ Recirc Air control wires so unplug the wires from the control unit.
6. There are 3 screws holding the next section of the Heater / AC control housing to the main blower unit. Only one is clearly visible; the other two are almost impossible to spot, and in fact I actually took two other screws out and because I did not have the right ones, when I started pulling the unit out I broke the two mounts off. The parts I needed were only $35 at the dealership. FYI - the screws are at the 10 O'clock, 1 O'clock, and 4 O'clock positions.
7. Once removed, you will be able to look in the space and see the blower fan, but not the blower motor itself. You are done on this side of the car (for now). Go over to the driver's side and remove the driver's seat.
8. Seat out??? Good. Next, find a 40lb bag of mulch, fertilizer, or something similar to lay in the space where the seat was. There is a frame member the seat bolts to that is raised so that laying on your back with your head under the dash is very uncomfortable after 7 seconds. The bag can be molded to make your stay in this position comfortable enough to perform the final dissassembly tasks.
9. Lay on your back with your head under the dash as far as possible. If you haven't cleaned your carpets in awhile you may want to do this before laying there.
10. With your left hand (right for RHD cars), reach up and feel for a ring that holds the blower motor in place. For those who need a visual first, get a short flashlight and look for it first. Inside the ring's circumference there will be a wire plug for 2 wires. You will need to squeeze the retaining clips on each side and remove the wire plug.
11. Next, there is a small molded translucent tube that plugs into the blower motor. This is a duct to channel some cooling air into the motor. Disconnect it from the blower motor.
12. Last, the ring has a small flange that needs to be flexed away from the motor so that the ring can be turned counter-clockwise. Once turned, the ring will fall into your hand and the blower motor assembly will fall away. go to the passenger side again and you can stick your hand into the blower cage and slide the assembly out.

Assembly:

1. Before putting in the new blower motor assembly, check inside for debris and clean if necessary.
2. Dealers wanted close to $200 for a fan assembly but I purchased one for $60 on-line (god bless the internet). Make sure you are getting the whole assembly and not just the motor.
3. Assembly is basically the reverse of dissassembly, but for the first part you will need an assistant unless you want to invest heavily in the Mazda speciality tool.
4. There are notches on the blower motor that match the heater unit case and the retaining ring. See how the ring fits on the motor before putting the assembly in the heater unit.
5. From the passenger side, fit the new blower assembly into the heater unit and make sure it is aligned with the slots and is all the way in. Once you are sure, have your assistant hold the motor in that position, taking care not to let it slip out of position.
6. Go to the driver side and assume the position on your back. Take the ring and align the slots. Make sure you don't push too hard against your buddy holding everything in place. Once on, turn the ring clockwise until it locks in place with a "click".
7. Plug in the little cooling tube and wire plug.
8. Make sure no loose wires are present. I left everything plugged together with the fuse panel so I can test the new blower before putting together everything else. If you are sure there is nothing that can short out, reconnect the battery negative terminal (don't need to tighten), turn on the ignition (but don't start the car!) and turn on the fan switch. Everything working??? Fan runs on all speeds??? Great!
9. Now, disconnect the battery again and reassemble everything else.
10. Reconnect the battery (tighten) and enjoy your new blower motor!!!