Ford Mustang: 11 Common Problems (Useful Guide)

First introduced in 1964, the Ford Mustang is the longest selling nameplate in the Ford line-up. 

Known for its stylish looks, high-powered engines and superior handling, the Mustang is one of the most iconic cars ever made. 

Owning one of these high-octane muscle cars is a privilege, however like all vehicles it does not come without its problems.  

We have outlined some of the most common issues on the Mustang to date. Let’s dive in! 

Ford Mustang Beeping 

Mustang owners found their vehicle was beeping at them while driving due to a faulty airbag warning lamp in the gauge cluster. This typically happens on 1994 – 2004  models. However, a door or trunk could be open, the parking brake is engaged or there is an issue with the airbags.

Some Mustang owners have found their vehicle would beep at them randomly with no obvious reason whatsoever. 

Before assuming the worst, always check to ensure your vehicle’s doors and trunk are closed properly and there are no obstructions that could be keeping them slightly ajar. 

Another detail worth addressing is the engagement of the parking brake.  Driving with the parking brake engaged can also cause the vehicle to constantly beep, so be sure to check it is disengaged – this will also prevent premature wear on your brakes. 

The Ford Mustang also has a feature that notifies the driver if the turn signal has been on for a long time, so if you forget to cancel your turn signals after a lane change, the Mustang will beep. 

Placing excess weight (such as groceries) on the passenger’s seat might trigger the seatbelt system to assume there is a passenger present, who does not have a seatbelt fastened. To circumnavigate this simply fasten the passenger’s seat belt.

After reading the possible causes mentioned above, and finding that nothing is obviously wrong, the beeping may be a warning that your airbags are faulty or your airbag warning system has a faulty light.  

If your airbag system has a fault that the control module has detected, a warning light on the dash will be illuminated.  

Over time, the airbag malfunction indicator lamp may burn out. When this happens, the system will audibly beep or chime instead, further warning the driver of a fault that needs addressing.  

A simple way to verify this is to turn your key in the ignition to the ON position and observe the gauge cluster, all lamps should illuminate, including the airbag lamp, and if it doesn’t you will receive an alarm.

If there is no light for the airbag warning in the dash when you turn the key on, then by replacing the light bulb this should solve your problem.

This issue is most common on 1994 – 2004 model year Mustangs, but can happen on other model years as well. 

If you find the airbag or SRS system has a fault, have it repaired immediately. 

You may also be interested in our article: Ford Mustang Beeping? (6 Causes & Solutions)

Ford Mustang Alarm Going Off Randomly

The most common reason your Mustang’s alarm is going off randomly is a weak car battery. Other causes may include a faulty hood switch, door switch, key fob, or the control module itself. Also, if your alarm system is aftermarket, improper installation could also be to blame. 

In some circumstances, Mustang owners will find their alarm may have been triggered via the Active Alarm System as this can go off from high winds, loud noises or accidentally by other people.

Anti-theft systems come standard on all new Mustangs. There are two  types of anti-theft systems on Mustangs, called “passive” or “active”. 

Passive anti-theft or PATS, uses a key with a transponder (a device that upon receiving a signal emits a different signal in response) in the head of the key. Each transponder is coded with a unique ID code without a correct signal the motor simply won’t turn. Known as a passive system because it doesn’t require any input from the driver.

Active alarms are used to help protect against unauthorized vehicle entry and the theft of parts and content. It is essentially made up of an interior motion detector and tilt alarm. Different modes will allow the monitoring of doors, hood, trunk and interior movement.

In an effort to help, we’ve outlined a detailed list of some of the possible reasons your Mustang’s alarm is going off at random: 

Weak Battery 

The 12V battery is the power source for all electronics in the Mustang. A weak battery can cause all sorts of issues for the security system, including activating the alarm.  

Whenever facing this issue, always have the battery tested first, and replaced if needed. 

Defective Hood/Door Switch 

The hood and door switches play a key role in the security system. If the  hood or a door is forcibly opened when the vehicle is locked, the switches prompt the system to sound the alarm. 

However, if the hood and/or door switches are failing, they may set off the  alarm, even if forced entry has not taken place. 

Faulty Key Fob

The key fob is responsible for arming the anti-theft system when the lock  button is pressed, and triggering the alarm when the panic button is pressed.  

Sometimes, the panic button on the fob breaks internally or becomes jammed in place, causing the alarm to activate intermittently. Even if this is not the case, the fob could still be the reason the alarm is going off. 

Ensure you have a healthy key fob battery. The batteries in key fobs are basically known as “watch batteries”. They will vary in size based on model year, but should still only cost around $5. 

Inoperative Anti-Theft System Control Module 

The Anti-Theft System Control Module is a computer that monitors the data for the security system, and triggers the alarm or prevents start-up based on the data it receives. 

Although it is rare, sometimes a faulty module can be the reason the alarm is randomly going off. 

RepairPal states the average cost for a Ford Mustang anti-theft system control module replacement is between $653 and $667. 

Improper Installation of Aftermarket Alarm System

Due to the technical nature of electronics, we recommend seeking out a reputable automotive electrician if you are experiencing problems with an aftermarket alarm system.

Newer Mustangs come standard with an anti-theft system in place, with active anti-theft packages available too. 

However, older Mustangs do not have anti-theft systems, so an aftermarket alarm system may have been installed. 

Aftermarket alarm systems are notoriously installed improperly by the inexperienced. This can create all sorts of issues. 

Related: Ford Mustang Alarm Going Off? (9 Causes & Solutions)

Ford Mustang Won’t Shift Out of Park 

A complaint from Mustang owners is that their car won’t shift out of park. This is commonly caused by parking on a steep incline without proper use of the parking brake, which damages the pawl. A defective brake pedal switch, shift interlock solenoid, or shift cable could also be to blame.

There could be a variety of reasons why your Mustang doesn’t shift out of park, the most common reasons are outlined below.

Damaged Pawl

Whenever you park a Mustang with an automatic transmission on an incline or steep hill, you are running a risk of transmission damage if you don’t exercise caution.

The parking brake should always be applied first when parking on a hill before shifting the transmission into the park position. When you are ready to drive away, always shift the transmission to the neutral position before releasing the parking brake.

Failure to do so can result in difficulty pulling the transmission lever out of park – this indicates that the pawl, a metal arm responsible for jamming the car’s transmission and preventing it from moving – has become damaged, it is often accompanied by a grinding noise.

Unfortunately this can often require costly repairs.

If your Mustang is currently stuck in park the vehicle may need to be rocked out of place, or the pressure taken off of the pawl before the shifter will move. 

Faulty Brake Pedal Switch 

The brake pedal switch activates the brake lights when the brake pedal is pressed.

It is also a safety device, used to ensure the driver is pressing the brake before the vehicle will allow you to pull it out of park. 

When the brake pedal switch is defective, safety interlocks will prevent the driver from shifting out of park. 

A quick way to check if it is working, is to check the operation of the  brake lights, no brake light could indicate this as the root cause. 

Defective Shift Interlock Solenoid

The shift interlock solenoid is the device that physically operates the mechanism that locks or unlocks your shifter.

It will enable when the brake pedal switch is depressed. 

When the solenoid is faulty, the shifter cannot move out of park. However, this can be bypassed, by removing the cover near the shifter and placing the key inside.  

RepairPal estimates the cost of replacement for a shift interlock solenoid is between $229 and $247. 

Broken or Seized Shift Cable 

The shift cable is what links your shifter to your transmission. Although it is a robust component, sometimes it will fail. 

If it breaks completely, moving the shifter will not move the transmission out of park.

But if it is seized, the shifter will be hard, if not impossible to move.

Either way, your Mustang won’t go very far until the cable is replaced. 

Ford Mustang Won’t Start/Clicking Noise 

The number one reason a Ford Mustang makes a clicking noise and won’t start is a weak or dead battery, however battery terminals should be cleaned and checked for tightness. Other causes include the starter motor itself or a poor electrical connection in the ignition circuit.

Starting system fault diagnosis can be costly, both in time and money. So, when dealing with a Mustang that refuses to start, the first place to check is always the battery. 

The main function of the 12V battery is to start the engine. If the battery is low on charge or has degraded, then it should be tested and replaced if necessary. The lifespan of a battery is finite and typically lasts around 5 years. 

Additionally, always make sure electrical connections to and from the battery are tight and free of corrosion. This is often overlooked by those who are diagnosing a vehicle that won’t start. 

If the battery is in good shape, the next place to look would be the starter motor.  

The “click” could be coming from an ignition relay in the fuse box, but if it is coming from the starter solenoid, then you know the solenoid is functioning. 

Starter motors can be tested as well and should be tested before they are replaced. RepairPal states the average cost for a Ford Mustang starter motor replacement is between $283 and $363. 

The worst-case scenario, would be the engine has seized. If an engine  runs out of oil, it can become seized, which means it will no longer spin.

This can cause the starter solenoid to “click”, but the engine won’t turn over and spring to life.

Make it a habit to regularly check engine oil level, and top up if needed. A seized engine requires replacement/rebuilding, and is extremely costly.  

Ford Mustang Won’t Reverse 

A Ford Mustang transmission that does not go into reverse may require extensive repair work performed by a specialist. However, you can always make sure the transmission has adequate fluid first, and top up as needed because low fluid could be the source of the problem.  

Transmissions are composed of many complex parts, including gears, shafts, solenoids, pumps, and so on. 

The complexity of transmission design usually implies the repair will be complex too, for this reason we recommend taking your vehicle to a reputable mechanic. 

With that said, we’ve still created a list of possible causes as to why your transmission is faulty.  

Before assuming the worst however, always make sure the  transmission has the proper amount of fluid, as well as the proper type of fluid in it. 

Automatic Transmission Won’t Reverse 

  • Faulty shift solenoid 
  • Broken reverse band 
  • Damaged clutch
  • Damaged seals 

Manual Transmission Won’t Reverse 

An updated kit including internal transmission parts is available to fix the “shifting into reverse” problems experienced with the Ford Mustang T-45 manual transmission. A link to the patented updated part is here.   

Some manual transmission owners have found by putting the transmission into 5th and slightly letting out the clutch, they were able to get it into reverse afterwards. 

Ford Mustang Key Not Detected 

A “key not detected” issue on the Ford Mustang is generally contributed to a dead fob battery, however, interference or a faulty fob can be the cause of this problem. If you are stranded, try inserting your fob in the cupholder and starting it. 

Almost all “key not detected” complaints were the result of a dead fob battery.

Batteries for key fobs are normally cheap (approximately $5) however, wave interference from certain wireless electronics can cause the fob not to be recognized by the vehicle. 

The fob or the module itself can be responsible for failure, albeit rarely.  

In any case, you can still start the vehicle when the fob is not detected by inserting the fob into the cup holder and pressing the start button.

Ford Mustang Won’t Unlock 

Usually when a Mustang won’t unlock, it is caused by a dead fob battery. However, other causes may be faulty fob, defective door lock actuator, broken lock cylinder, or damaged/seized door lock cables. 

Having a Mustang that does not unlock can be worrisome. Don’t fret though, because even if your key fob is not working, you can still unlock the door by other means. 

On the latest generation Mustang, if you open the fob up, you will find a  key inside. Insert the key into the bottom of the outer door handle. 

If the key does not go into the lock cylinder, or the lock cylinder does not turn, then a defective lock cylinder or cable is probably the source of your problem. 

But if it won’t unlock by means of the fob, then either the fob battery is dead, or the door lock actuator is faulty. 

Ford Mustang Radio Not Working 

When Mustang owners encountered the issue of their radio being inoperative, the majority of them fixed the issue by performing a “hard battery reset” (disconnecting the battery for 15 minutes). However, if this does not fix the issue, it could be fuse-related, faulty circuitry, or the radio itself. 

When the radio does not work on your Mustang, it can make your driving  experience dull to say the least. 

Sometimes, a quick fix does the trick, such as disconnecting the vehicle’s  battery for about 15 minutes.

Think of it like resetting your router at home when your internet isn’t working. Sometimes, electronics just need to be reset in order to function  properly. 

Otherwise, a bigger issue may be at play. Sometimes a fuse could have blown due to a short in the wiring, or a damaged power wire could be preventing it from starting up. 

Another issue is the motherboard of the radio itself, having broken solder joints. 

Either way, it’s hard to tell how long or expensive the repair could be, as  there are many factors that could cause an inoperative radio. 

If your vehicle is under 36,000 miles you should be covered by Fords Bumper to Bumper warranty and so your best option would be to contact your dealer.

Ford Mustang Bluetooth Not Working 

If your Mustang’s Bluetooth is failing to connect or disconnects frequently, try deleting your device from the list of paired devices, and re-pairing them. Also ensure your device is compatible, and up to date on software. 

Some Mustang owners found their Bluetooth would act up, particularly  when trying to connect. 

If the phone is already paired, a simple fix may be to delete the device  from the device list, and re pair them again. 

However, if the issue still persists, ensure your device is Bluetooth compatible, and the Bluetooth settings are enabled both on the vehicle and on the phone. 

There are updates available for newer model Mustang’s radios, and phone updates should be done as well if all else fails.

iPhone’s are particularly prone to causing connectivity issues when they do not have the latest version of iOS installed.

Ford Mustang Screen Not Working 

When the screen appears blank or refuses to turn on, the first thing to try would be a system reset. Hold the power button and next button at the same time until the pony appears. If all else fails, you may be dealing with a blown fuse, faulty screen or other electronic faults. 

As stated earlier in this article, sometimes electrical devices need to be reset after failing to work. 

The audio unit screen on the Mustang is no exception. This can be done by either holding the “power” and “next” buttons at the same time or disconnecting the battery for 15 minutes. 

If this fails to work, some owners found by disconnecting their Bluetooth, or their phone from USB, the screen would come on. This is possibly because the system is overloaded when trying to configure the phone during start-up.  

For this reason, it is recommended to wait until the system is completely loaded to plug your phone in, or connect it to Bluetooth. 

Check with your local Ford dealership to see if any updates are available for the audio unit.  

With electronics, you could be dealing with damaged wires or circuitry. That’s why it is always recommended you take the vehicle to a reputable automotive technician when dealing with such issues. 

If your vehicle is under 36,000 miles you should be covered by warranty and so your best option would be to contact your Ford dealership.

Ford Mustang Won’t Take Fuel

A Ford Mustang that won’t take fuel is a common problem on Mustangs with a “saddle style” fuel tank. This is a known issue on Mustangs, with a lot of documentation. The most likely cause of this is an obstruction in the EVAP system, such as a clogged charcoal canister. 

If you notice your Mustang takes fuel very slowly or not at all, you’re not alone. Many Mustang owners have experienced this issue and it is documented in great detail. 

The issue stems from the EVAP system being clogged. The EVAP system is responsible for recirculating the fuel vapours back through the engine,  to be burned. 

Although the most common cause is a blocked charcoal canister other areas to investigate may include: 

  • Fuel Filler Neck  
  • Fuel Vapor Control Valve  
  • Fuel Tank Pressure (FTP) sensor 
  • Canister Vent Solenoid 
  • EVAP Canister Purge Valve 

Having a mechanic properly inspect these components is the only way to have your Mustang taking fuel properly again. 

References: 

BEEPING:

https://www.allfordmustangs.com/threads/beeping-noise-no light.194769/ 

https://themustangsource.com/forums/f670/argh-dang-beeping-no reason-410986/ 

https://www.stangnet.com/mustang-forums/threads/how-do-i-get the-airbag-beep-to-stop.524127/ 

https://www.moddedmustangs.com/threads/air-bag-system-is beeping.280213/ 

ALARM: 

http://www.formust.com/anti_theft_system-36.html 

https://repairpal.com/estimator/ford/mustang/antitheft-system control-module-replacement-cost 

https://mechanicbase.com/electric/car-alarm-keeps-going-off/ https://mustangforums.com/forum/v6-s197-general discussion/623498-factory-alarm-issue-warning-randomly-goes off.html 

https://www.cargurus.ca/Cars/Discussion-t24812_ds438643 STUCK IN PARK: 

https://www.cargurus.ca/Cars/Discussion-d2_ds489503 https://www.corral.net/threads/automatic-wont-shift-out-of park.445844/ 

https://www.700r4transmissionhq.com/ford-mustang-stuck-in-park/ https://repairpal.com/estimator/ford/mustang/auto-trans-brake shift-interlock-solenoid-replacement-cost 

NO START/ CLICK 

https://mustangforums.com/forum/classic-mustangs-tech/621077- won-t-start-just-clicks-have-video.html

https://www.stangnet.com/mustang-forums/threads/clicking noise-when-trying-to-start.843501/ 

https://repairpal.com/estimator/ford/mustang/starter-replacement cost#:~:text=Ford%20Mustang%20Starter%20Replacement%20Co st%20Estimate&text=The%20average%20cost%20for%20a,priced %20between%20%24200%20and%20%24258. 

REVERSE 

https://patents.google.com/patent/US20080302195A1/en https://www.corral.net/threads/t-45-reverse-permanent-fix.1139525/ https://www.justanswer.com/ford/1ieqo-2005-ford-mustang-when put-reverse-will.html 

https://www.justanswer.com/ford/5y9e7-ford-mustang-06-mustang will-not-move-reverse-goes.html 

UNLOCK 

https://www.youtube.com/watch?v=4uJTwsiIgnI

RADIO 

https://mustangforums.com/forum/2005-2014-mustangs/733270- 2014-radio-problems.html 

https://www.mustangevolution.com/threads/radio-is-not working.375366/ 

SCREEN 

https://www.mustang6g.com/forums/threads/base-stereo-screen-is black-blank.76049/

FUEL 

https://www.allfordmustangs.com/threads/fuel-tank-fill-problem resolution.108623/