Question about 2003 Chevrolet TrailBlazer

1 Answer

Blower control module

I have 2003 chevy trailblazer that keeps burning out the blower control module. I have put 3 in this month. I can't turn the blower down or off. Even when the car is turned off the only way to stop it is to pull the fuse under the hood.

Posted by on

  • showdowne808 Jan 18, 2009

    I thought there was a relay also, or a resistor, but evidently it's all controlled by that module. The manual doesn't show a relay or resistor. After replacement, (of the module) it works for about 20 miles, then shorts out again.


1 Answer

  • Level 1:

    An expert who has achieved level 1.


    An expert that hasĀ over 10 points.


    An expert whose answer gotĀ voted for 2 times.

    Problem Solver:

    An expert who has answered 5 questions.

  • Contributor
  • 16 Answers

There should be a relay for that blower. sounds like the relay is stuck. see if you can find out where it is and replace it. You should find that info in a service manual for that vehicle. hope this helps: )

Posted on Jan 17, 2009

  • Jeremy Stringer Jan 19, 2009

    ok, well it sounds like you know more about this problem than I do,lol. I would study the wiring diagram, there has to be something else going on there. sorry I couldn't help.


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Missing variable control voltage on the blower fan control module on a 2008 Buick lucerne

What are you using to test this control signal ? Were you on right wire ?
Blower Motor Control Processor The blower motor control processor is an interface between the HVAC control module and the blower motor. The blower motor speed control, battery positive voltage and ground circuits enable the control processor to operate. The HVAC control module provides a pulse width modulation (PWM) signal to the control processor in order to command the blower motor speed. The processor supplies 12 volts to the blower motor through the blower motor voltage supply circuit. The control processor uses the blower motor ground as a low side control to adjust the blower motor speed.

Chevy Trailblazer EXT Blower Motor Won Turn Off The blower motor in this video don't shut off , but he show's how to test the PWM signal right !
Your blower motor control module is probably bad , or HVAC control panel is bad , or a wiring problem !

Sep 26, 2016 | 2008 Buick Lucerne CXL

1 Answer

I have a 2003 trailblazer EXT LT. the front AC/ Heat controls work when they want to. they fan will run after the car has been turn off for as much as 3 hours. or it will not work at all. I checked the fan...

If you have automatic climate control, replace your blower control module, behind the glovebox.
If it's manual, replace blower motor resistor assembly, same location.

Feb 15, 2011 | 2003 Chevrolet TrailBlazer

1 Answer

2003 trailblazer back air stays on after the truck is turned off

hi, there is a technical service bulletin published by general motors about these trailblazers and this problem, it is very common to have this problem if you own one of these. the rear a/c module is located on the passenger side in the very back underneath the plastics and bezels in the back. there is a blower resistor module that controls the fan speeds and recieves input from the control panel that gets too hot and melts the plastic surrounding the wiring connector and allows the terminal inside the connector to short the fan control wire to battery power. if this is the case, you will have to replace the resistor module, the wiring and connector, and sometimes the blower motor. you should contact you local gm/chevy dealer for parts though, they have the wiring pigtail so you replace just the connector end, and the new style resistor module, and if i remeber right, i think there is a air shield in the kit to install to improve air flow inside across the resistor to help cool it down. the blower motor when running produces the cooling ability for the resistor, if there was no airflow across the resistor, it would overheat almost immeadiatly. take the rear plastics off and the rear seat out, and have a look, you should be able to find this problem pretty quickly.

Jun 23, 2010 | 2003 Chevrolet TrailBlazer

2 Answers

A/C won't shut off when I push off button.


Aug 23, 2009 | 2003 Chevrolet TrailBlazer

3 Answers

2003 Chevy Trailblazer AC won't turn off

Check on and off switch it may be defective.

Jun 29, 2009 | 2000 Chevrolet Impala

2 Answers

2003 Chevy Trailblazer my AC blower won't turn off!

you have a short to power which will cause it to stay on constantly check your blower motor resistor pack to ensure that it is working and check the wires going to the blower to make sure you have a power and a ground

Jun 29, 2009 | 2004 Chevrolet TrailBlazer

2 Answers

2003 Chevy Trailblazer - Rear Heat/AC Controls Don't Work

Sorry, I don't have an answer, but have the same problem. Did you ever figure out what was wrong?

Apr 16, 2009 | 2003 Chevrolet Tahoe

Not finding what you are looking for?
2003 Chevrolet TrailBlazer Logo

490 people viewed this question

Ask a Question

Usually answered in minutes!

Top Chevrolet Experts


Level 3 Expert

63801 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

21990 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

6812 Answers

Are you a Chevrolet Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides