Help with Air Conditioner on 94 Q

Post by **AlabamaDan** » Fri Oct 22, 2004 4:35 am

Hey guys,

Long time for me, but I could use some help. The AC/Heat in my 1994 Q only works when the fan is on the highest speed. The temperature works fine. All the other features work great. It will only blow when the fan is on high. It used to work once in a while on the other speeds, but no longer. What do I need to replace or troubleshoot?

Any help/advice is appreciated.

Thanks,Danny

Post by **metaverse3** » Fri Oct 22, 2004 9:04 am

I believe the issue is with the blower motor resistor. Replacing this unit will fix the issue where the fan works on high. It is also called a fan/blower amp unit..

Post by **natsoundup** » Fri Oct 22, 2004 9:09 am

about a 65-70 part from Joe at Scottsdale.. common problem..... takes about an hour to take out..

Have to take out glove box....it's no big deal...

don't even think about taking it to the dealer....

Post by **Jesda** » Fri Oct 22, 2004 11:44 am

http://www.q45.org/cleanevap.html

Post by **AlabamaDan** » Thu Oct 28, 2004 10:37 am

Jesda,

Are you posting a pic of the blower motor resistor that I need to change. I followed the link and it talks about cleaning the A/C evaporator or are you telling me that all I need to do is clean the evaporator?

Is this problem with the blower motor resistor common? Have others had the problem and fixed it by replacing said resistor?

Sorry to be so dense, but it's been years since I did much to a car myself.

Post by **wlong** » Thu Oct 28, 2004 11:04 am

Danny:

The fan control amp is the almost rectangular part in the center of this photo. The link describes how to clean the evaporator by removing this part to access the coils. I just ordered this part from Joe (Part number INF-27761-85E01) and the cost was around $60. My specific problem is addressed in another thread with this part as the fix. My problem is that the fan runs on high speed whenever the car is on - even when the climate control system is off. I can't tell from your post if this is the same problem. This part apparently contains the resistors that reduce the fan speed. That explains why it is embedded into the air box (for cooling). When this part fails, the fan defaults to high speed.

I should get the part this week and I'll let you know if the fix works and any problems with the installation.

W. Long

Post by **Jesda** » Thu Oct 28, 2004 11:18 am

Sorry, I left out the caption. Its my understanding that the cause of the problem is the big silver object in the middle of the picture, sometimes referred to as a fan speed sensor.

If I'm wrong, someone please chime in.

Post by **Q45tech** » Thu Oct 28, 2004 4:06 pm

"cause of the problem is the big silver object in the middle of the picture, "

No the cause of the failure is the motor drawing too much current overheating the transistors causing them to fail, but most do the temporary fix of replacing just the transistors. And buying some time.

Just like the bad fuel pump motor causes the FPCU to fail!

Post by **Jesda** » Thu Oct 28, 2004 4:25 pm

Can the blower motor be removed and cleaned every year for longetivity, or does it make no difference in how long it lsts?

Help with Air Conditioner on 94 Q

Help with Air Conditioner on 94 Q

Re: Help with Air Conditioner on 94 Q (dannymchale)

Re: Help with Air Conditioner on 94 Q (metaverse3)

Re: (Jesda)

More info

Re: (Jesda)

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