Blower Control Module Issue?

[ReattaMatt89]

Hello friends,

The blower motor in my 89 suddenly stays on, even when the ignition is off.  Once upon a time I believe I read here that the culprit is the Blower Control Module, and that one of the members here might have some nice used modules.  Thoughts? 

 

Thanks in advance for your assistance.

 

Matt

[MCHinson]

ReattaMatt89,

Welcome to the AACA Discussion Forum. I have moved your post from the AACA General Forum to the Reatta Forum. I am sure that you will quickly fine an answer here.

[Dave Henderson]

I can't help by furnishing you a module, but will offer up my experience with the same problem on my '93 LeSabre.  It took some investigating to find where the module was located, I finally went to a Buick dealer and the parts guy found an illustrated parts breakdown showing it located in the depths of the heater plenum, not a nice place to have to go.  Next, the part cost about $165, 10 or so years ago.  I decided to try to get one at a junkyard, and hit paydirt.  "Crazy Ray's" was a U-pick yard with very low prices.  I found 2, and paid $6 apiece.  Just this past November the first one gave out and I am on #2 now, hoping it lasts out the car. 
In the mean time while looking for a deal on a module you could disconnect the wires to the heater fan.  They were exposed and easy to find on my LeSabre.  Good luck.

[89RedDarkGrey]

Yes, the module is bad. Replacement is easy. Remove the long black plastic cowl "wing", and on passenger side is the 2 plugs, with screws.

 

HVAC BLOWER MODULE

 

[Jim]

I have tested good used blower control modules available.

Jim

[harry yarnell]

I too have good (tested) control modules. $30 plus ship.

I'm in Maryland.

[Barney Eaton]

Here is where they are on Reatta and Riviera (probably in a similar location on other GM cars)

The module is item #1

When you take it out.....look inside the hole and you will see the front of the evaporator.

It quite likely has crud on it and with a shop vac and a old tooth brush you can clean it off and greatly improve the airflow to the inside of the car.

Also if you purchase a replacement, new or used you can test it by plugging in the two connectors before removing the bad one.

New ones are expensive

In the future, if the fan motor continues to run, by unplugging the connector (either one) on the controller, the motor will not run.

Edited April 27, 2017 by Barney Eaton (see edit history)

[harry yarnell]

Bear in mind, the blower may not come on IF the cabin temp is warmer than when what's set for HEAT, or cooler than set for A/C.

[ReattaMatt89]

Thanks for the quick responses and all of the input, fellas.  That back screw was a bit of a challenge, but I was finally able to get the unit out.  

Quite a bit of crud on the evaporator coil, as mentioned.  I plan to fashion an adaptor to the shopvac and see what can be done about that.  I'll keep you posted.

 

Thanks again.  

8 hours ago, Jim said:

 

 

[2seater]

It is easier to clean the evaporator if you also remove the blower motor assembly. That gives two points of access so you can shine a light in as well as see from the top. Also an alternate access for the vacuum.

[ReattaMatt89]

Ah, yes.  That makes sense; should make it easier to get in there.  Thank you for that tip.

[Barney Eaton]

I have a solution to get light into those tight places......find an AC cord with a small socket on the end....these are used for Christmas decorations and those candles people put in their windows.

A 7 watt night light bulb works well but the new LED's don't get hot and have a whiter light.

These small bulbs can be dropped into small spaces and give plenty of light.

[89RedDarkGrey]

 

[ReattaMatt89]

Removed the blower motor, cleaned the evaporator and installed the new Blower Control Module today.  I'm back in business and ready for the Texas summer.

 

Thank all of you for your advice and video links.  I sincerely appreciate the help.