Chevy Trailblazer Climate Control Problems [9 Common Issues]

You’ve always enjoyed driving your Chevy Trailblazer because the climate control system worked perfectly. But now, your climate control is acting strangely, and you’re worried about losing the comfort in your car. So, you want to know how to fix the problem.

By continuing to read, you’ll learn the common climate control issues in Chevy Trailblazer cars and how to go about them. I’ll also give you some tips to help you prevent similar problems in the future.

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Chevy Trailblazer Climate Control Problems

If your Chevy Trailblazer climate control system is bad, here are some issues you may experience:

1. Blower Fan stops working after contact with speed bump

If your blower fan stops working every time you hit a speed bump, your Chevy Trailblazer climate control system is bad. This problem may occur because some wires on the blower motor have come loose.

To fix this issue, you’ll need to remove the loose connections and replace them. But first, you should confirm that the blower motor has loose wires.

You’ll find your blower motor behind the trim panel under the glove box. Study the back of the blower fan for any loose connections. If you find any faulty wires, change them.

However, if you don’t see any loose wires at the back of the blower fan, there might be a worn shaft in your blower motor.

Usually, blower motors with worn shafts make a lot of noise. So, if your blower motor is noisy, its shaft might be torn. In that case, you’ll need to replace the motor.

Your blower fan should be back to normal after you’ve changed your blower motor.

2. Heater blows cold air on driver’s side/AC blows hot air on driver’s side

A common sign in faulty Chevy Trailblazer climate control systems is that the heater blows cold air on the driver’s side. You may also get hot air on the driver’s side when you turn on the AC. In contrast, the passenger side always blows air at your desired temperature.

If the heater in your Chevy Trailblazer keeps blowing cold air on the driver’s side, your driver’s side blend door actuator might be broken. Changing the blend door actuator should fix this problem.

Your driver’s side blend door actuator is located in a large plastic box below the driver’s dashboard.

3. Driver’s side vent is static on heat or AC for several days

If your driver’s side vent keeps blowing cold/hot air for several days, even after you’ve changed the temperature, your climate control system is problematic.

You might be facing this issue because your driver’s side vent is malfunctioning. To resolve this problem, you’ll need to reset your climate control system to its default settings. This will eliminate the functional error in the system and restore it to its original condition.

Here’s how to reset your Chevy Trailblazer to its default settings:

Press and hold the front and rear defrost buttons simultaneously.
Hold these buttons for 10 seconds.
Then, release them.
Now, press the front and rear defrost buttons again. This should turn off the defrost settings.

Your driver’s vent should start working properly after this.

4. Heater not blowing enough air

If your heater isn’t blowing enough air, you might have a bad climate control system. The most likely culprit for low airflow from the climate control is a bad blower motor.

The blower motor is the component that pushes air from your climate control system into your vehicle’s seating area. So, if this motor is bad, you’ll barely get any air from your HVAC unit.

If your heater isn’t blowing air properly, the first thing you should do is change the blower motor. You’ll find your blower motor behind the trim panel under your glove box.

But if the problem persists after you’ve replaced your blower motor, your car battery might have low voltage. Use a multimeter to check if your battery has enough voltage.

We recommend using the T-pin prober or Bed-Of-Nails insulation piercer to measure the voltage on your Chevy Trailblazer battery.

If the multimeter confirms that you have low voltage, you’ll need to charge your vehicle’s battery. After charging your battery, check if the heater is blowing air properly. If you still aren’t getting enough air from the heater, your mixer motor might be broken.

As time passes, the gears on your mixer motor get shredded, thus causing the motor to malfunction. Your heater should start blowing properly after you change your mixer motor.

But if replacing your mixer motor doesn’t fix the issue, your control panel might be dead. As such, you’ll need to get a new control panel for your car.

5. Fan doesn’t respond to controls

If your blower fan doesn’t come on when you press the control, your Chevy Trailblazer climate control system is problematic. The fan may later turn on and go back off when you aren’t pushing any controls. Some fans even keep working after you’ve turned off your engine.

This problem may occur because you have a faulty blower resistor.

When you press your fan’s switch, the blower resistor is supposed to send electrical currents to the fan and get it to turn on. But since your blower resistor is malfunctioning, it may transmit electrical current to the wrong path. This might be why your fan doesn’t turn on immediately after you press the fan switch.

After a while, your faulty blower resistor may regain its bearings and transmit the current to the blower fan. But this will only last for some minutes, as the resistor may develop a short circuit and divert the electrical current to the wrong place again.

Change your blower resistor to resolve this issue. You’ll find your blower resistor under the blower motor. The blower motor is located below the glovebox in your car.

If your fan still doesn’t respond to its controls after you’ve replaced your blower resistor, you might have a bad ambient temperature sensor. Your automatic climate control system uses information from this sensor to control the temperature of your car.

Perhaps your fan doesn’t turn on because the ambient temperature sensor hasn’t informed your climate control that you’ve pressed the fan’s switch. But a broken ambient temperature sensor doesn’t only fail to deliver information to the climate control system.

If your ambient temperature sensor is faulty, it may also transmit wrong information to your HVAC unit, like telling the unit to activate the fan when you haven’t pressed the switch. This may cause your climate control system to switch on your blower fan when you haven’t prompted it.

You can fix this problem by replacing your ambient temperature sensor. The ambient temperature sensor is located near your front bumper.

6. Climate Control System only blows air on high driving speed

If your Chevy Trailblazer climate control system only blows air on high driving speed, you may have a bad blower resistor.

Your blower motor, which blows air to your car, relies on your blower resistor for power at low driving speed.

But when driving fast, the force on your vehicle’s engine is heightened. This lets the engine provide enough current to your blower motor that it doesn’t need the blower resistor to function.

If you want your climate control to blow air at lower speeds, you’ll need to replace your blower resistor. The part number for a Chevy Trailblazer blower motor resistor is 15-80906.

7. AC only blows through floor vents

If your AC blows air through floor vents, but won’t blow through the dash vents, your climate control system might be problematic.

Your AC may fail to blow air through the dash vents because you have a faulty mode door actuator. This actuator determines the vent which air flows through at a particular time.

Once you replace your mode door actuator, your climate control system may start blowing air through your dash vents. You’ll find your mode door actuator at the top left area of your climate control case.

8. External temperature reading keeps fluctuating

Another way to tell that you have a faulty climate control system is if your external temperature reading keeps fluctuating. When you encounter this problem, the external temperature readings that appear on your temp meter are usually wrong.

Wrong external temperature readings are often caused by a bad ambient temperature sensor. Since this temperature sensor is in charge of gauging temperature, an error in the sensor could cause an incorrect temperature reading.

To fix this issue, you’ll need to replace your ambient temperature sensor.

9. Climate control display often goes blank, and HVAC functions stop working

You can be certain that you have a broken climate control system if the display often goes blank. Immediately after the display goes blank, all your temperature functions may stop working.

If none of your HVAC controls work after your climate control display goes blank, your HVAC fuses might be blown. As such, you might need to change your fuses to resolve this problem. Your HVAC fuses are located in the under-hood fuse box.

When inserting the new fuses, make sure they fit snugly into the fuse box. Otherwise, your HVAC display may go blank again.

Another reason your climate control display and climate controls may stop working is a rusty HVAC wire. If the wires on your climate control system are corroded, they might be cutting off power to the system.

Check the back of your climate control case for rusty or loose wires. If you find any slack wires, remove them and replace them with new ones.

If your climate controls stop working after you’ve replaced the rusty wires, your compressor relay might be the culprit. Without a good relay, your AC won’t get power to function. This might be why your temperature doesn’t change when you turn the temperature dial.

Consider replacing your AC compressor relay to fix this issue.

Chevy Trailblazer Models with the Most Climate Control Problems

The Chevy Trailblazer models with the highest number of climate control problems are the following:

2002 Chevy Trailblazer
2005 Chevy Trailblazer
2004 Chevy Trailblazer

According to carcomplaints.com, the 2005 Chevy Trailblazer is the most notorious model for climate control problems. Sixty-three users of the model reported AC/ heater issues in their cars.

Other models with the most climate control problems are the 2002 and 2005 Chevy Trailblazer, which garnered 25 and 34 complaints, respectively.

Chevy Trailblazer Models with the Least Climate Control Problems

These are the Chevy Trailblazer models with the fewest climate control problems:

2009 Chevy Trailblazer
2013 Chevy Trailblazer
2014 Chevy Trailblazer

Statistics from carcomplaints.com shows that no user of the 2009, 2013, and 2014 Chevy Trailblazer models complained about climate control issues.

How Much Does It Cost to Fix Chevy Trailblazer Climate Control Problems?

It costs between $249 – $705 to fix the average Chevy Trailblazer climate control problem.

Tips to Prevent Chevy Trailblazer Climate Control Problems

Recharge your AC once a year.
Wash your car daily to reduce rust.
Fix climate control issues as soon as they occur
Charge your car battery at least once in 2 months.
Always park your vehicle under a shade.

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Wrapping Up

If you’ve encountered any of the signs discussed here, apply the recommended solution as soon as possible. However, if you can’t seem to locate a faulty part or detach it from the vehicle, contact your dealer.