On this page, you’ll find a short video outlining two common causes of an irritating clicking sound from your dashboard area.
Click…click…click, I thought it was just me. No, I couldn’t drive a car like this either. I’d have to figure it imminently, if not sooner.
Anyhow this page is all about helping you figure it out. The video does a fair job at giving you a flavor of the likely causes. They are of course not the only causes, below you’ll find a few mechanics tips for locating the root cause and you’ll also find some tools to make the whole job move along like organic butter.
Mechanics Top Diagnostic Tips
Here’s where I give you my tips for finding the root cause of the click sound without stripping half the dashboard and with just minimal tools. I like to begin with a top-down detective approach, which often saves a ton of wasted time and unnecessary stripping.
Before we begin diagnosing, as an ex-GM technician we were trained to first verify that the customer complaint (that’s you) is actually complaining about a real fault and not a normal operating condition of the vehicle. Now, for many, this isn’t relevant because you know your vehicle like the back of your hand.
But for some, the vehicle might be new and all vehicles are different. Various clicks and otherwise strange noises from under the dash area are quite normal as components like relays, electric steering, HVAC climate control systems, control modules, circuit breakers such as electric window switches do their thing.
It is worth considering if the vehicle is new to you, just maybe this sound is normal behavior.
Okay with that out of the way, here’s some diagnostic tips that will help:
- Use your ears to narrow the field of search. Place a finger on actuators and or relays with the symptom present and feel for the tell-tale vibration.
- Recall when the condition first presented. Does it coincide with any noteworthy events?
- Operate HVAC controls, steering wheel, seat heaters, electric seat controls, etc, to see how it affects the symptoms.
- Are symptoms present all the time or only during adverse weather conditions.
- Does it coinside with using brakes, backing up, towing, early morning cold starts etc.
- Use a battery maintainer to keep battery in good shape while diagnosing with the ignition system on.
When you think on these questions a while and you’ve got nothing, then it’s time to roll sleeves.
Lost HVAC blend door settings
As you know disconnecting the battery without keeping the control modules alive may cause some HVAC issues. If that sounds like your issue, ie you’ve recently changed the battery or had a flat battery and need to boost start your vehicle, then Bingo!
You’ve very likely already found the root cause – Lost blend door settings. To fix it you’ll need to recalibrate the system.
Calibrating usually requires a shop-level scan tool, you’ll find one listed below. Otherwise, you’ll need to visit a local shop. You can try operating all the heater controls slowly to help the HVAC control module locate the blend door locations.
Blend door actuator
Faulty Blend door or Actuator
A faulty blend door actuator is high on the list also. The actuator moves the heater matrix blend doors or flaps in relation to where the internal heater controls are set. The actuators are stepper motors that by their nature allow for very small motor movements referred to as steps or counts.
A couple of issues are likely, either the motor is weak and has failed and is causing a clicking sound or the blend door has become stiff which causes the actuator motor gear to slip and wear causing a click sound as it operates.
To fix this the actuator will need to be identified and replaced. Your HVAC system will have lots of actuators and so you’ll need to have the symptom present (clicking) while you place a finger on each actuator in turn, to feel for the tell-tale vibration.
Expect 4, 6, 8, actuators and more depending on how sophisticated your HVAC system is.
If you need a new actuator, check out the Amazon HVAC actuator link below.Amazon HVAC Actuators
A relay is as you know used widely in auto electrics. They are used to control high-demand circuits using a low-demand circuit. And so they are used widely in switched circuits.
Relays a pretty durable but they do fail. A relay sounds an audible click as the contacts close and a circuit completes, this is normal behavior.
It is possible your clicking sound is caused by a faulty relay or a faulty relay circuit. Finding and swapping out the relay is a great way to eliminate it as a possible root cause. And like the HVAC actuator we spoke of earlier, placing a finger on each relay in turn when the symptom is present is a great way to locate the relay in question.
While not all relays are the same many are and finding another identical relay in the same vehicle is common, it’s OK to swap one for another for the purpose of testing. Alternatively, I’ve listed a relay tester below.
The Autel MaxiCOM is a shop-level tool. It is capable of reading, clearing fault codes, coding a new battery, placing EPB module in service mode, and calibration after the repair. It is also capable of activating ABS modulator solenoids when performing a full brake bleed procedure. Picture links to Amazon.com.
Fast, simple, and inexpensive relay tester. Tests four and five-pin relays display green light for good and red for fail. Picture links to Amazon.com.
Schumacher OBD-L Memory Saver or KAM tool. Important to fit the memory tool before disconnecting the battery. Modern cars don’t like being without power. The Schumacher is easy to use with its 3 steps guided procedure. Picture links to Amazon.com.
The NOCO genius battery charger is what’s known as a smart charger also known as a battery maintainer or trickle charger. They are smart because they detect the battery state of charge and automatically turn it off and on as needed. Picture links to Amazon.com.
A head-mounted lamp is like having a third hand a real advantage when you are doing battle. This rechargeable LEd head-mounted lamp is conveniently sold and delivered by Amazon.com.
- About the Author
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John Cunningham is an Automotive Technician and writer on Rustyautos.com. He’s been a mechanic for over twenty-five years and has worked for GM, Volvo, Volkswagen, Land Rover, and Jaguar dealerships.
John uses his know-how and experience to write fluff-free articles that help fellow gearheads with all aspects of vehicle ownership, including maintenance, repair, and troubleshooting.