If there’s one car feature that would be hardest to give up on a cold winter morning, it’s got to be remote start. Nothing beats walking out to an already warm car with defrosted windows and a toasty interior.
But when you press that button and nothing happens, the disappointment is real. Let’s look at why your remote start isn’t working and how to get this valuable feature back online.
How Remote Start Systems Work
A remote start system is more complex than just a starter motor and a button. For safety reasons, these systems have multiple components and checks that must all work together perfectly for a successful remote start.
The basic components include a control module (the “brain” of the system), a key fob transmitter, various sensors throughout the vehicle, and a receiver that picks up the signal from your key fob.
Factory-installed systems are integrated with your car’s computer, while aftermarket systems require additional wiring and components such as a bypass module to help “bypass” the engine immobilizer or other factory security system.
Before allowing your car to start remotely, the system runs through several safety checks. It verifies that:
- The doors are locked
- The hood is closed
- The transmission is in park
- The check engine light is off
- The security system is armed
- The brake pedal isn’t pressed
Factory systems come pre-installed and are specifically designed for your vehicle model. These typically have better integration with your car’s existing systems but may have shorter range than aftermarket options.
Aftermarket systems can be installed in almost any vehicle and often offer extra features like longer range or smartphone control. However, they require professional installation to avoid interference with factory security systems and to make sure all safety features work correctly.
See Also: 7 Causes of Heated Seats Not Working
Common Reasons Why Remote Start Fails
1) Dead Key Fob Battery
The most common and simplest reason your remote start won’t work is a weak or dead key fob battery. When the battery starts getting weak, you may notice the remote start feature working intermittently or requiring multiple button presses. Other key fob functions like door locks, will also become less reliable and the remote’s range will significantly decrease.
Many key fobs will display a warning light (on the fob itself or on your dashboard) or emit a different beep tone when the battery is low. If your key fob has been working fine but suddenly becomes inconsistent or stops working completely, there’s a good chance the battery is to blame.
How to Fix
Replacing a key fob battery is a simple DIY job that typically costs under $5. Most key fobs use CR2032 or similar button batteries available at many retailers (e.g., grocery stores, department stores, office supply stores, pharmacies, or online retailers like Amazon).
You’ll need to carefully pry open the key fob case. Typically, there will be a small slot somewhere, where you can insert a coin or flathead screwdriver. Replace the battery, making sure the positive side faces the correct direction, then snap the case back together.
If you’re not sure how to open the fob, check your owner’s manual or search YouTube.com for the correct procedure for your vehicle. Here’s an example:
2) Safety Requirements Not Met
Remote start systems have built-in safety checks that must be satisfied before the car will start. If any one of these conditions are not met, remote start simply won’t work. The two most common issues are leaving your hood open after checking the oil or having an unlocked door.
Some vehicles also require you to use a specific starting sequence, like pressing the lock button before the remote start button. If your car starts normally when you’re sitting in the vehicle but won’t respond to remote start, there’s a good chance one of these safety requirements isn’t being met.
Some vehicles will flash their lights in a specific pattern to indicate which requirement is preventing the start.
How to Fix
First, verify all doors, the hood, and trunk are fully closed and locked. Make sure the transmission is firmly in park (sometimes it can be slightly out of position even if it feels like it’s in park). If you haven’t yet used remote start, check your owner’s manual for the correct remote start sequence and any specific requirements for your vehicle.
This is typically a no-cost fix that just requires attention to detail. If the system still won’t start after confirming all safety requirements are met, you may have a faulty switch or sensor that needs professional diagnosis.
Related: Car Door Won’t Fully Close? (Here’s Why)
3) Check Engine Light Is On
If your check engine light is illuminated, the majority of remote start systems will automatically disable themselves. This is true for both factory and aftermarket systems.
The reasoning is sound: if there’s an engine problem serious enough to trigger a warning light, it’s safer to prevent remote starting until the issue is resolved. The same applies if your car’s computer detects any transmission, security system, or critical sensor faults.
Sometimes your check engine light might be on for something minor like a loose gas cap or a small emissions leak. Unfortunately, the remote start system can’t decipher the stored diagnostic troubleshooting code to tell the difference between minor and major problems.
Even if your car runs perfectly fine with the key, that check engine light will still prevent remote starting.
How to Fix
You’ll need to diagnose and fix whatever is causing the check engine light first. Start by having the codes read. If you have access to a diagnostic scanner, it’s easy to do. If not, many local auto parts stores will do this for free.
Minor issues like a gas cap might cost nothing to fix, while more serious problems could range from $100 to $1000+. After the repair, the check engine light needs to be cleared.
If you’re comfortable using a code reader, you can buy a good basic one (like this) for $30-50. Otherwise, most repair shops charge about one hour of labor (typically $80-150) to diagnose and clear codes (even though it only takes a few minutes).
4) Range/Signal Interference Problems
Remote start issues can often be traced back to signal problems between your key fob and the car. Most factory systems work reliably up to about 30-300 feet, while aftermarket systems might reach 1000 feet or more.
If your remote start works inconsistently or only at very close range, you might have an interference problem or a weak transmitter. Common sources of interference include large metal buildings, power lines, and other electronic devices.
Some vehicles use a small antenna mounted inside the windshield or under the dash for receiving remote start signals. If this antenna gets damaged or disconnected, your range will be severely limited.
Weather (like heavy rain, snow, or fog) can also impact signal strength and reduce your effective range. In rare cases, other nearby vehicles using similar frequencies can cause interference.
How to Fix
Start by testing your remote start at different distances and locations to rule out environmental interference. If range is consistently poor, the antenna might need inspection. Factory antenna replacement typically costs $100-200 plus labor ($80-150). Aftermarket system antennas are usually cheaper, around $30-80 plus installation.
If you’re comfortable working with car electronics, antenna replacement can be a DIY job, but accessing the mounting location can be tricky. Poor range can also indicate a failing key fob transmitter. The solution of programming a new transmitter isn’t cheap, often running hundreds of dollars (depending on the vehicle).
5) Programming Issues
Lost or corrupted programming is a surprisingly common issue with remote start systems. This can happen after a battery replacement, computer update, or sometimes for no apparent reason.
Your key fob needs to maintain a proper “handshake” with your car’s computer to work correctly. If this programming gets disrupted, your remote start might stop working even though all the components are physically fine.
Some vehicles require you to periodically “refresh” the programming by starting the car normally and letting it run for a set amount of time. Others might need to relearn your key fob if the car’s battery was disconnected.
Programming issues often show up suddenly. Your remote start may work perfectly one day and then completely fail the next.
How to Fix
Basic reprogramming steps vary by vehicle but usually involve a specific sequence of key turns, button presses, and timing. Your owner’s manual may have the procedure but sometimes a comprehensive service manual is required (some cars let you reprogram fobs yourself at no cost).
If that doesn’t work, you’ll need dealer programming. Expect to pay anywhere from $50-300 for basic key fob reprogramming (higher end vehicles naturally being at the top of that range). For more complex issues involving the main remote start module, costs can reach $200-500.
Aftermarket systems might need a visit to the original installer, with similar costs depending on the problem’s complexity.
6) Security System Conflicts
Remote start failures can often be traced back to conflicts with your car’s security system. In some cases, the security system might think there’s an attempted theft when you use remote start.
This is especially common with aftermarket systems that weren’t properly integrated with the factory anti-theft system. Even factory remote starts can have security conflicts if the system gets confused about the key’s location or authentication status.
These issues are more common after replacing key fobs or having security system work done. Sometimes the remote start will work for a while, then suddenly get “locked out” by the security system.
Clues include your security light flashing differently than usual, or the car might make different sounds than normal when you try to remote start. Some vehicles will flash specific error codes through the dash or exterior lights.
See Also: 9 Reasons Why Your Car Alarm Is Randomly Going Off
How to Fix
The fix depends on whether you have a factory or aftermarket system. For factory systems, a dealer reset of the security system usually resolves the issue, costing $100-200.
Aftermarket systems might need reprogramming or rewiring by the original installer. If the systems are fundamentally incompatible, you could be looking at $200-500 to upgrade or modify the remote start to work properly with your security system.
Basic security system resets can sometimes be done at home by following a specific key cycle procedure in your manual.
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