06 Trailblazer--blower will not shut off


Augdog74
01-11-2011, 07:16 PM
When I turn the engine off on my Trailblazer, there is a fan under the dash that continues to run. It sounds like the blower fan. I ended up having to pull the number 34 fuse out to make it stop. This fuse is labeled as "Ignition A". If I pull the #35 fuse, which is for the blower fan, it doesn't stop it. Is there something else besides a blower fan under the dash making this noise and why?

danielsatur
01-11-2011, 08:30 PM
Try Isolating unswitched Bat fuse's until fan turns off.

Augdog74
01-11-2011, 08:58 PM
Try Isolating unswitched Bat fuse's until fan turns off.

I noticed the blower doesn't work at all with the #34 fuse pulled. I might also add that the outside temp is below 0, so I don't know if that has something to do with it?

danielsatur
01-11-2011, 09:09 PM
Some control modules, use a Capacitor as a battery with the ignition off.
The Cap inside of the control module is probably shorted, thus using BAT from the Auto.

maxwedge
01-12-2011, 03:18 PM
The blower relay/resistor up behind the glove box is the usual source of this problem, also look at the connector to this component for melted contacts.

Augdog74
01-12-2011, 08:11 PM
The blower relay/resistor up behind the glove box is the usual source of this problem, also look at the connector to this component for melted contacts.

Is this part easy to get to?

Augdog74
01-12-2011, 10:05 PM
Ok... I found it and got it out. Is there anyway to test this component to find out if it is the problem? I see no indication of any melted wires.

MT-2500
01-13-2011, 07:22 AM
Ok... I found it and got it out. Is there anyway to test this component to find out if it is the problem? I see no indication of any melted wires.
Make sure you got right one.
Did blower quit when you pulled it.
Substitute a known good one with same no and see if it works right.
Let us know how it goes.

Augdog74
01-13-2011, 11:54 AM
Make sure you got right one.
Did blower quit when you pulled it.
Substitute a known good one with same no and see if it works right.
Let us know how it goes.

I didn't have the fuse in when I took it out, but I assume it wouldn't work anyway beings the wires were disconnected from the fan? Am I right?

MT-2500
01-13-2011, 12:09 PM
I didn't have the fuse in when I took it out, but I assume it wouldn't work anyway beings the wires were disconnected from the fan? Am I right?
You can not tell much about the problem if fuse out.
If the fuse was in and blower motor is stuck on and you pull relay and blower quits then you know you are at right relay.
Put a know relay in and see if blower works right.

Augdog74
01-20-2011, 09:10 AM
I replaced the blower control module and all is good. Thanks for all the help!

Shay B
10-09-2012, 01:56 PM
How hard and expensive is it to replace the blower control module?

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