The Acura MDX is the upscale equivalent of the Honda Pilot.
It comes with lots of luxury features and state-of-the-art tech, however it may beep for unknown reasons.
In this article, we’ll help you get to the root of these beeping sounds.
Table of Contents
Why Does My Acura MDX Keep Beeping?
The most common cause of beeping on an Acura MDX is related to the auto-lock walk-away feature. Other causes include the seatbelt sensor, a key fob left in the car, a door is open whilst driving, headlights on, a light bulb is blown in the gauge cluster, key fob low on battery and safety features.
Auto Lock Walkaway
The most common cause of beeping on an Acura MDX is related to the auto-lock walk-away feature.
As the name implies, when you walk away your MDX automatically locks itself as long as you have the key fob on you.
However, If you walk away too quickly then the MDX will beep to warn you that the vehicle isn’t locked.
Try adding a slight pause before walking away from the vehicle and make sure the panel/computers are completely shut down.
Alternatively, just open and shut the door again – this has worked for some owners.
The auto lock feature may fail to lock if:
- You close the hatch or a door and walk away too soon before it is fully closed
- You have a failed lock or sensor.
- You mobile phone or other electronic devices could be interfering with the smart entry remote signal.
- You left a fob in the car
- A door, the hood or the rear hatch is not closed properly
- You walked away from the vehicle too quickly – stay within 5 feet of the vehicle when you get out and close all the doors and then wait until you hear a second beep before walking away.
What Does The Owners Manual Say:
The auto lock function activates when all doors and tailgate are closed or all doors are closed and tailgate begins power close operation, and the keyless access remote is within about 5 feet (1.5 m) radius of the outside door handle.
Exit vehicle while carrying keyless access remote and close door(s) and tailgate.
- While within about 5 feet (1.5 m) radius of the vehicle. -> The beeper sounds; the auto lock function will be activated.
- Carry the keyless access remote beyond about 5 feet (1.5 m) from the vehicle and remain outside this range for 2 or more seconds. -> Some exterior lights flash; the beeper sounds; all doors and tailgate will then lock.
Under the following circumstances, the auto lock function will not activate:
- The remote is inside the vehicle -> The beeper will not sound.
- The remote is taken out of its operational range before all the doors and tailgate are closed. ->The beeper will sound.
How To Enable/Disable Auto Lock Walkaway:
- Using the touchpad, select settings from the main menu.
- Select ‘Vehicle’
- Select ‘Keyless Access Setup’
- Select ‘Walk Away Auto Lock’
- Select either ‘Enable’ or Disable’
With Auto Lock enabled, when you exit the car with the fob and all the doors and tailgate are shut properly, the car will beep once whilst you’re still in close proximity.
Then, when you are at least 8 feet away it will beep again to signal that everything is now locked.
Listen for both beeps to be certain it’s locked.
Most Common Causes of Acura MDX Beeping
The main common causes for an MDX that beeps are:
1. Auto Lock Walkaway
See the above sections for more details.
2. Fob Still In The Car
If you’ve left a key fob in your MDX, you may hear a warning beep.
3. Car Is Not In Park
If you turn the key off and open the door without manually putting the vehicle in park, the vehicle will be left in accessory mode and may sound off a series of rapid beeps.
4. Headlight Switch In On Position
Make sure the headlight switch is in OFF or AUTO. Otherwise, it’ll beep at you – the beep is faster than the seat belt caution.
5. Door Is Open Whilst the Car Is Running
Ensure all car doors, the trunk and hood and firmly and properly closed.
6. Seatbelt Sensor
Another common cause for beeping is related to the passenger seatbelt sensor.
The sensor itself may be broken or it might be triggering a beep if there is weight on the passenger seat such as groceries or your pet dog.
A simple test for this will be to fasten the seatbelt and see if the noise stops.
It’s a good idea to ensure all doors and the rear hatch are shut properly too.
7. Accessory Plugged in 12V Outlet
Sometimes your MDX for whatever reason won’t like some of the accessories you plug into the 12V Power Outlet.
Some owners have found by disconnecting their charging devices/electronics from the outlet the beeping has ceased.
8. Gauge Cluster Bulb
If a bulb blows in your gauge cluster then your MDX may start beeping at you to try and signal that there is a problem.
It’s hard to alert this issue to the driver otherwise.
This could be an airbag warning light that’s gone out, so just have a thorough inspection of the light on your gauge cluster to make sure there lit up properly.
The best time to do this is just as you turn the key in the ignition and everything should come on.
9. Lane Departure Warning
If your MDX is equipped with LDW then you can have a beep included as a warning and this is normal.
10. Road Departure Warning
Road Departure Warning is designed to beep also, this is completely normal, it may even pull the steering to get you back on track.
11. Low Key Fob Battery
A low key fob battery can cause a number of issues including random beeps and even triggering your car alarm.
Try giving the fob a clean, remove any dirt/dust/grime and replace the battery.
12. Seat Memory
Some MDX owners have had success at getting rid of unknown beeps by resetting their seat memory – also known as the Driving Position Memory System.
How to reset the seat memory will vary depending on model year so it’s best to look in the owner’s manual for how to do this.
13. Electronic Devices Inside or Outside of The Car
The beeping may not actually be coming from your MDX. Do you have any other electronic or battery-powered devices in your vehicle that could be causing the beeping? Usually, it’s their batteries going bad.
For example a garage door opener or a dropped wristwatch.
14. Electrical Issues
If your MDX has developed an electrical fault or a there is a wiring issue, it may beep as a result of this.
This can be quite difficult to diagnose if there obvious warning messages and the best thing to do is visit your local Acura dealer.
Acura MDX Beeping When Door Open
If the light switch is ON then this will trigger beeping when the driver door is open. Make sure the headlight switch is on OFF or AUTO to avoid beeping.
You may notice this after getting your car back from the valet as sometimes they need to adjust switches to clean them properly.
4th Generation Acura MDX models are designed to beep when the driver’s door is open.
This is a normal function of the car and as far as we can tell, it cannot be disabled.
Acura MDX Multiple Beeps / Beeps 3 Times
Multiple beeps are usually related to the Auto Lock walkaway, feature.
See the first section where we cover this in detail.
Acura MDX Not Beeping When Locked
If your Acura MDX does not beep when you lock the doors, this means that the Keyless Lock Answer Back feature is turned off.
When you exit your MDX and lock it using the fob, you have the option of having beeping ‘on’ or ‘off’. This can be adjusted using the Keyless Lock Answer Back feature.
This can be set from the display unit.
- Go to ‘Settings’
- Select ‘Vehicle’
- Select ‘Door/Window Setup’
- Select ‘Keyless Lock Answer Back’
If it’s on ‘Off’ the car will make no sound when you lock it.
If its ‘On’ it will beep and the exterior lights will flash when you lock it.
Acura MDX Beeping While Driving
The most common cause for an MDX that beeps whilst driving is the seatbelt sensor. If there’s weight on the passenger seat this can trigger the alarm, or if the seatbelt sensor is faulty this will trigger it too.
Try buckling the passenger’s seat belt.
It’s also a good idea to make sure all the doors and the rear hatch are closed properly.
If all of these conditions are met, the problem could lie in a defective door switch, leading the MDX’s electronic system to think a door is open while the car is in motion.
Some owners have suggested disconnecting the battery for an hour to see if that clears any possible errors.
Acura MDX Chirping Noise
If there’s a strange chirping sound coming from your MDX’s engine then this could well be related to the fuel you are using.
This is a common problem across several Acura and Honda models.
Some owners have noted that this is to do with fuel that contains ethanol and the sound is normal – the ethanol in the gas makes the fuel pump make that sound.
This problem is accentuated though if you use low-quality, cheap gas.
Changing the fuel pump will likely not make the noise go away.
So we advise trying higher quality gas, failing that it’s best to speak to your dealership.
Acura MDX Tailgate Beep
Some MDX owners are not too happy about the loud beeps that accompany opening and closing the tailgate.
This beep is apparently for safety reasons and thus has been designed so it can’t be turned off or have the volume adjusted.
Some owners however have suggested the following workarounds.
- Disconnect the wire to the speaker.
- Covering the speaker with electrical tape or foam
Remember that this appears to be the same ‘beeper’ that sounds when you lock the doors with the remote so make sure you really want to reduce the sound.
Here’s what an owner on mdxers.org had to say
“Since it was so annoying to me I found the buzzer and covered part of it so it wouldn’t be so loud…so far I’m very happy with the volume…Here’s what I did just in case someone else is interested. This will also affect the volume of the keyless access beep. I know it can have some drawbacks but it works for me.”
“The buzzer is located right in between the back bumper and the spare tire (right in the center) so if you lay down under the spare tire you will be able to see…you can pull the cable out then the buzzer no tools needed.”
Check for Recalls or TSBs
By entering your car’s VIN number on Acuras recall page or the NTHSA’s Safety Issues & Recalls page you can determine whether or not there is a TSB or recall for your vehicle and if there is you’ll want to get it addressed.
A recall is issued by a vehicle manufacturer for issues that are safety-related, while a TSB covers components that may be malfunctioning but don’t compromise the safety of the vehicle.
Disconnect the Battery
Sometimes mysterious alarm problems can disappear with a simple reboot, there are no guarantees here but it’s worth a try.
Disconnect the battery for 20 seconds and this resets many of the electronics in the vehicle.
Check For Warning Messages
When the alarm occurs can you see any lights or warning messages on the instrument panel?
This can give a clue as to what’s causing the beeps e.g. ‘Door Ajar’.
Take it to an Acura Dealership
If needed, take your Acura to the dealership.
Tell them you are NOT paying for a check on what the problem might be.
Ask them if they will check it for free.
Most dealerships and other places do quick/initial diagnosis for no money as they plan to make money for the repair of your vehicle.
If your unit is still under warranty then they should fix and resolve the issue for free.