2003 Infiniti I35. Recently the A/C blower motor had a bearing wear out. My wife kept running the blower even though it make an awful racket, and eventually the motor quit running. Yesterday I tried to install an Autozone (provided) blower motor. The replacement motor bolted right in place, but it did not have the built in plug like the original blower motor - it just had a positive and negative wire lead. I installed a spade terminal onto the hot wire for the motor and plugged it into the factory plug-in connector (hot wire), then connected the ground wire to a ground (the motor would not run when I tried to use the second plug / slot as a ground).

The problem is that the blower motor runs full speed as soon as the ignition key is turned on, and the dash fan controls do not affect the operation of the blower motor at all.

I believe that I do not have the motor connected correctly but that was the only way I could get it to run.

Is there possibly something else going on here, like possibly a burned out resistor that controls the four fan speeds? Regards,Inline 6

Yeah, you're right on the money. Sounds like you bypassed the blower motor control amplifier, which uses a variable resistor to control the fan speed. Without the amplifier, the fan will run at full speed (I think it's actually a little higher than "max" through the HVAC controls) any time accessory power is on.Or, it's possible you wired it correctly and the amp is bad, as the system will bypass it when it fails. Bad blower motors do put a greater load on the amp, which can cause premature failure, so that's certainly possible.

This section of the service manual contains wiring diagrams for the HVAC system which should help you verify that you've wired things up correctly.

And welcome to NICO!

Thanks a bunch - especially for your quick response!

Looking over the info you provided - initially I am leaning towards a burnt amplifier.

Soon as I find out I will get back so the forum members can see how things worked out or me.

Thanks again,Inline 6

There is a posting by "Skibane" in the Q45 forum on how to repair the Fan Control Amplifier. Can save you a lot of money if you have electro-mechanical aptitude.

zer...ifier

loystock,

Thanks for your help. Using Skibane's post I found that the high temperature circuit was blown.

Until I can buy another component I soldered a jumper in place.

Thanks again to all who helped.

Inline 6

It's our pleasure to help members. NICO is the best car club on earth.

Had motor problems with my 02 I35 too. Changed out blower motor today and wire to factory plug and everything is gggd to go.

Hey guys,

New to the NICO board. I have a 2002 I35, and found this posting. I was having similar problems, and still am, and wondered if you might be able to help.

Started off with the blower motor going out (display would indicate blower was running, but nothing happened). Bought a replacement at Autozone. As I think I saw on this posting, the Autozone part only had an orange wire and the black ground. When I wire the orange blower motor wire to both the original wires in the I35, and ground the black, the the blower now works, but only blows on MAX speed, even if I turn the A/C off. Basically, looks like I fixed the blower issue, but now either created another issue or something else is wrong.

I saw in the post that you may have had the same issue. What did you end up doing to fix the problem?

And to let you know, I am an ABSOLUTE novice at car repairs, and know little to nothing about the wiring stuff. I've sunk A LOT of money into this car recently, so was trying to avoid any further major expenses and also try to learn how to fix some of this stuff myself.

Thanks in advance for any help/advice you might be able to give.

The blower motor must be hooked up properly to run at the desired speed. One side of the blower (Pin 1, W/L wire) is connected to the Blower Relay contact (Power) while the other side (Pin 2, L/W wire) is connected to the Fan Control Amplifier (FCA) a.k.a Resistor or module. The Blower Relay enables power to the blower with Ignition ON while the FCA controls the speed and path to the ground. If you ground 1 side of the blower, then the FCA is bypassed and the blower will always run at FULL speed whenever the Ignition is ON.

You must connect the blower wires to the respective terminals - blower relay and FCA. If the pins are connected properly and the blower is still not running or only at a certain speed or full speed, then the FCA is bad and needs to be replaced or repaired. The FCA repair is covered in the earlier posting.

Notwell,

Provided you have no other problems (such as I did) all you have to do is connect the orange wire into the original factory connector plug (check first to make sure you are connecting to the half of the plug that is the hot wire), then connect the black wire into the other.

I simply used a spade connector on the end of the Autozone blower wire and "plugged" them in.

Hope this helps.

Inlne 6