If your car makes a noise, it may be an indication of a problem. It is often a minor issue, but you must find out the reason for the sound and if it can lead to a major problem. For example, one of those sounds which make your brows furrow is the clicking or knocking sound from the dashboard. It can be very erratic sometimes and compels you to think, “Why Is My Dashboard Clicking?”
In this guide, you will learn all about the noise, its reasons, and how to fix them.
Causes Of The Clicking Or Knocking Noise
Your dashboard houses your HVAC system, and most probably, there is a problem with it that may make such noise. The common causes of the knocking sound can be-
- Your heater control module has lost calibration
- The stepper motor is having problems
- There is a faulty relay
Let’s address these causes, their diagnosis, and ways to fix them.
Heater Control Module Calibration
Your AC and heating system occupy most of your dashboard. It is called Heating Ventilation Air Conditioning (HVAC). It is a complete package that has blended doors, motors, fans, and a system that operates based on accurate readings and sensors. When any part of this system fails or this control module loses calibration, it makes a clicking noise. The solution is recalibration..
To understand the problem completely, you must first understand the different parts of the HVAC unit.
- Heater Unit– This unit holds all the parts of the HVAC system inside it.
- Temperature sensors– These sensors send the live report to the controller to regulate the heat.
- Heater Core– It can be understood as a small radiator that routes coolant through the small tubes and radiates heat into the car cabin.
- Blend Doors- These doors open and close as per the operator’s instructions to pass the air.
- Fan– Fan is located behind the heater core and blows air on it. It warms the air before it enters the cabin.
- Stepper Motors– They work as an intermediary between blend doors and control module, informing the latter one about the exact position of the blend doors.
- Control Module- This module receives inputs in the form of positions and temperatures and follows the operator’s commands.
Now you must understand that if the blend doors are not working properly, causing stepper motors to send incorrect signals, the control module malfunctions. The reason for lost blend doors can be faulty stepper motors, if the doors are stuck, if the stepper motor was disturbed, flat or disconnected car battery, etc.
To fix this problem, you need to recalibrate your HVAC system. It is a time-crucial process, and you must keep a watch handy to do it.
The steps are described below:
- Turn on the ignition.
- Then push the Auto button.
- Turn off the ignition now.
- Remove your HVAC fuse for one minute precisely.
- Now turn on the ignition again and let the system do its work. Stay away from controls for two minutes and let the system relearn.
- Turn on the ignition for 15 seconds and then start the engine.
The recalibration process is complete. It will work for most cars, but some cars may have another sequence. Now, turn on your AC and see if the clicking noise has stopped or not.
Stepper Motor Issues
The stepper motor informs the control module about the blend door positions. It moves in precise motions and increments minutely. These increments are called counts. To know if you have a faulty stepper motor, you need a scanning tool which is not generally available with most car owners. So, you can try changing the AC settings and hear if it causes the clicking or knocking noise.
To check the problem, open the glove box and see if you have a stuck blend door. A faulty motor is a culprit if you find the blend door in the perfect position without any obstruction. It may need replacement. You can do it on your own, or you can take your car to the mechanic if fixing the vehicle while lying on your back is not appealing to you.
A Faulty Relay
Your car is full of different systems that work together and make your ride smooth. It requires several electrical circuits, motors, plugs, belts, pipes, relays, etc. A faulty relay can also be the cause of the clicking or knocking noise in the dashboard.
Today, cars are equipped with different technologies, which require several fuse boxes fixed here and there in your car. Each fuse box contains relays and fuses. A relay can be understood as a switch that breaks the circuit, control the heavy load with a low circuit, etc. Many circuits of your car use a relay switch such as wipers, power seats, horns, etc.
The power is sent to the relay from the control side, which magnetizes it. It flows through the copper armature and makes the contact points to close. It makes a brief click every time the contact points open and close. But in the case of a faulty relay, the clicking sound becomes more frequent.
To fix the relay, remove the fuse box. Now remove the relay and shake it. If it is faulty, it will make a rattling sound. Replace the relay with another one. It is simple. Look at the relay pins and if they are in their respective places, fix the new relay. Then, fit the fuse box in its place. Now, start the engine and see if it makes the clicking or knocking sound.
How To Diagnose A Clicking Or Knocking Sound?
Before you take your vehicle to the mechanic, it is important to listen to the sound carefully. Try to figure out the exact timing of the sound. For example, whether it starts as you start the engine when you change the AC settings, the exact location of the sound, etc. It will be beneficial for your mechanic to relay the exact timing and sound of the noise.
Listening to your car’s different sounds and noises can save you from a major repair cost in the future. If your car makes a clicking or knocking sound, don’t ignore it. Instead, ask, “what causes a clicking or knocking sound in the dashboard” and try to fix the problem or take it to your mechanic as soon as you can.