Blower Motor runs constantly

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Apr 2, 2007 | 04:31 PM

Reggie88

Thread Starter

3rd Gear

Joined: Mar 2007

Posts: 3

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Blower Motor runs constantly

1988 Corvette with the C68 electronic A/C control. Is the fault possibly the 3 inch square module on the right side of the evaporator case beside the blower motor under the hood? If So where could I get one of these. Is there a blower motor relay and where would it be located? Thanks for any help with this?

Apr 2, 2007 | 09:14 PM

CFI-EFI

Race Director

Joined: Sep 2000

Posts: 17,298

Likes: 33

From: The Top of Utah

Whatever you do, don't "fix it'. I can remember if it was the late 60's or the early 70's that GM went to constant (key "On") hvac blower motor operation.

RACE ON!!!

Apr 2, 2007 | 09:43 PM

jfb

Team Owner

Joined: Mar 2001

Posts: 54,124

Likes: 30

From: Cincinnati, Oh USA

A better description would help diagnosis. The blower control module (on top of the evaporator housing) gets a signal from the dash controller and supplies power to the blower motor. Ignition off, the blower motor should not run and if it does, the blower control module is defective.
It is normal for the blower motor to run, depending on the speed commanded by the dash controller EXCEPT when the dash controller is in OFF position.

Apr 2, 2007 | 10:44 PM

Electricblue80

Instructor

Joined: May 2006

Posts: 153

Likes: 0

From: Gautier MS

Where is the blower control module located?

Apr 3, 2007 | 04:06 AM

chevykevv

Racer

Joined: Oct 2006

Posts: 256

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From: Huntingdon Cambridge

I had a similar problem with my 89.
But the blower fan ran even with the engine off & key out of ignition.

Turned out to be the blower control module fitted on top of the blower fan.

Got one off ebay $49

Description: AC blower motor power module with part numbers of #15-72561 with 16061602 on the unit.

Don't know if this helps any?

Apr 3, 2007 | 08:19 AM

RWDsmoke

Drifting

Joined: Jan 2005

Posts: 1,354

Likes: 325

From: San Antonio Tx

The blower control module is located on top of the evaporator housing. It also controls the compressor. The same module was used on all GM cars with climate control for many years. I got one at pick-n-pull for $9.00 (half price day) off a '92 cadillac. (they almost all have climate control)

Apr 3, 2007 | 09:13 AM

Reggie88

Thread Starter

3rd Gear

Joined: Mar 2007

Posts: 3

Likes: 0

Blower runs constantly

All,
Thanks for all the timely feedback on this problem. I found the problem last night. I put the old module (ESC 203 (NAPA)) back in place on the right side of the evaporator case. Looking closer for a relay, I discovered the rubber hose from the back of the blower motor to the evap case was pulled off the evap case. I put it back on and the blower motor shut down. It fits a little loose so I tie wrapped it. All the blower control/speed/auto/heat works now.
Thanks Guys!!!

Apr 3, 2007 | 01:29 PM

Ray Quayle

- 1986 Original Owner -

Joined: Apr 1999

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From: North Yorkshire, England

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Quote:

Originally Posted by chevykevv

Got one off ebay $49

Kevv,
You didn't use the one I sent you then?

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Apr 3, 2007 | 10:59 PM

SunCr

Le Mans Master

Joined: Dec 2000

Posts: 7,839

Likes: 22

From: San Diego, Ca

Quote:

Originally Posted by Reggie88

You might want to check the electrical connector at the Blower Motor. All the hose does is provide cooling for the motor. Having it hooked up, or not hooked up, shouldn't shut off the motor. I'd wriggle it around to make sure there isn't an intermittent. Check for a discolored hot lead too which would indicate that it's dropping volts. You can improve that by taking the connector apart and soldering the terminals to the leads. You may have a faulty motor too. Easier to tell by seeing how many amps it pulling on high. Something north of 20 amps probably means it's worn out.

Apr 4, 2007 | 01:01 PM

#10

Reggie88

Thread Starter

3rd Gear

Joined: Mar 2007

Posts: 3

Likes: 0

Ok,
Sounds like good advice, will do this weekend.
Thanks

Apr 25, 2007 | 03:09 PM

#11

bowtie350_428

Pro

Joined: May 2005

Posts: 525

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From: San Antonio TX

Hey Reggie88, give us a follow up. Did you ever find out where to get a new blower control module? I have the same problem on my 91 (climate control a/c) but I have not had any luck on finding a replacement control module.

Apr 25, 2007 | 03:11 PM

#12

bowtie350_428

Pro

Joined: May 2005

Posts: 525

Likes: 0

From: San Antonio TX

Quote:

Originally Posted by RWDsmoke

RWDSmoke, did you have any problems using the blower control module from the 92 cadillac? I too am from S.A. and I may just have to make a run to pick-a-pull and hunt down a cadi if I can’t find a new unit.

Apr 14, 2014 | 01:29 PM

#13

lakeman208

4th Gear

Joined: Apr 2014

Posts: 4

Likes: 0

Blower runs all the time

Quote:

Originally Posted by jfb

Thanks, I replaced the module, and the blower stops, as it should, BUT now the wires that plug into the module gets REAL hot. I unpluged them so it wouldn't catch fire or melt. Have you had this condition ????

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