Has your remote start stopped working for seemingly no reason?  This can be frustrating but there’s usually a simple solution, you just have to know where to start.  In this post, I’ll give you some remote start troubleshooting tips for the 8 most common reasons why your remote start stops working.

While this post was written with Viper remote start systems in mind, they can apply to any Directed Electronics product and most all other common brands as well.


8 Remote Start Troubleshooting Tips

Below is a list of the 8 most common reasons why your remote start might have stopped working.  Read on for explanations on how to identify if one of these applies to your situation and how to fix the problem.

  • Toggle Switch in Off PositionChecklist
  • Hood Pin Open
  • Remote Batteries Need Replacing
  • Neutral Safety Wire not Grounded
  • Remote not Paired
  • Foot Brake Wire Resting at 12 Volts
  • Engine Sensing not Working Properly
  • Immobilizer Bypass Needs to be Reprogrammed

Some of the items on this list can be easily identified by the Viper system’s error reporting.  If your attempt to remote start the vehicle fails, you might see the parking lights flash a number of times.  This is your remote start system telling you what caused the failure to start. The table below outlines what all of the flash sequences mean.

FlashesPossible FaultSolution
5Brake inputRelease foot brake or check foot brake input wire.
6Hood pin inputClose hood or check hood pin wire.
7Manual Transmission Start (MTS) not enabledEnable MTS mode.
8Toggle switch offTurn toggle switch on.

1. Toggle Switch in Off Position

Toggle-SwitchViper remote start systems come with a toggle switch that gives you the ability to disable the remote start system at any time.  If you had your remote start system professionally installed, the installer should have let you know where they mounted the switch.

The toggle switch will only disable the remote start feature of your system.  If your system also has alarm and keyless entry features, they will still be functional with the toggle switch in the OFF position.

I’ve seen a lot of vehicles come into the shop for remote start troubleshooting and it turned out that the owner just accidently bumped the toggle switch into the OFF position.  The fix for this problem is to simply flip the switch back into the ON position.


2. Hood Pin Open

Hood-PinThe hood pin on a remote start system is a safety feature that temporarily disables the remote start when the hood is open.  This will prevent the remote start from activating if someone is working in the engine compartment.

There are several types of hood pins but the most common are the plunger type like the one shown in the picture.  They all perform the same basic function which is to provide a ground signal to the remote start system when the hood is open.

When the remote start “sees” a ground signal on the hood pin wire, it will disable the remote start features only, but other convenience features such as door locks will still be operational.  If your system has alarm functionality, you’ll also notice that the alarm doesn’t arm properly. This is because the hood pin is also an input that will trigger the alarm when armed.

When a viper alarm system doesn’t arm properly, it will give an additional chirp from the siren when you attempt to arm it if it sees a signal on any of it’s alarm triggers.

If you suspect you might have a faulty hood pin, you can visually inspect it to see if it is depressed when the hood closes on top of it.  Alternatively you can test continuity to ground on the hood pin wire when the hood is closed. The hood pin wire on a Viper remote start system is the grey wire.

If you’re not sure how to test for continuity with a digital multimeter, check out my post on Multimeter Uses and Functions – How to Use a Digital Multimeter.


3. Remote Start Batteries Need Replacing

If you don’t have a remote with a rechargeable battery, then your remote will use flat watch style batteries to power it.  The range that your remote will start your car from will diminish as the batteries start getting low and eventually it will stop working all together.

I’m sure this goes without saying but I’ll say it anyway…if the batteries in your remote are getting low, it’s time to replace them.


4. Neutral Safety Wire Not Grounded

The neutral safety wire on the remote start system is a safety feature designed to prevent the remote start from activating if the vehicle is in gear.  It connects to a wire in the vehicle that rests at ground when the transmission is in neutral. If the remote start doesn’t “see” ground on this wire, the remote start functionality will be disabled.

Not all vehicles have a neutral indicating wire so in many cases the remote start’s neutral safety wire is just connected to chassis ground.  And when a remote start is installed on a manual transmission vehicle, the neutral safety wire connects to the emergency brake wire.

You can test to make sure your neutral safety wire is getting a ground signal by testing continuity to ground.  The neutral safety wire on a Viper remote start system is the black wire with white stripe (black/white).


5. Remote Not Paired

RemoteThis doesn’t happen very often but on rare occasions I’ve seen remotes become unpaired from the system.  It’s hard to tell for certain if this is your problem but if you are getting no response whatsoever from your system, then it is a contender.  Start by replacing the batteries in your remote to rule out a dead battery, but if you still get no response then you might try re-pairing your remote.

Since there are different pairing procedures for different Viper remotes, I can’t give you a universal procedure to follow.  But you can find owner’s manuals for all Viper products here on their website. Just look up your remote start system’s model number and the manual will have the pairing procedure for the remote that it comes with.


6. Foot Brake Wire Resting at 12 Volts

The foot brake input wire on the remote start is a shutdown input that serves two functions.  It’s primary function is to allow the key to take over when you get in to drive the vehicle. When you get in, turn the key on, and press the brake to put the car in gear, the remote start shuts down but the vehicle stays running because the key is in the on position.

Its other function is as an anti-theft feature.  If someone tries to get in your vehicle while it’s remote started and drive off with it, they have to press the brake to shift it out of neutral.  Since they don’t have the key, the brake will shut the vehicle off.

The foot brake wire one the remote start gets a positive 12 volt signal from the foot brake wire in your vehicle when that brake is pressed.  If the wire is resting at 12 volts due to a short circuit or any other reason, it will prevent the remote start from activating.

You can test the foot brake wire with a digital multimeter to make sure that it is not at 12 volts when the brake is not pressed.  The foot brake wire on a Viper remote start system is the solid brown wire.


7. Engine Sensing Not Working Properly

TachometerDepending on the age of your remote start system, there are a few ways that the remote start can be programmed to detect when the engine has successfully started so it can stop cranking the starter.

Older Viper remote start systems had two options; tachometer (tach) sensing or voltage sensing.  Tach sense is the most reliable method. It uses a tachometer signal in your vehicle that indicates the engines RPMs.  Voltage sense monitors your vehicle’s voltage to see when the alternator starts generating a higher voltage than the batterie’s resting voltage.

Somewhat newer Viper systems have a third option available; virtual tach (I don’t remember exactly when this came out…somewhere around the 2010 timeframe).  Virtual tach works similarly to voltage sense but is much more reliable. It samples the voltage when you activate the remote start and continues to sample voltage hundreds of times per second to determine when the engine has started.

If one of these engine sensing options is not programmed properly or there are changes in your vehicle’s electrical system due to temperature or battery age, the remote start may not recognize when the engine has started.

When your system is experiencing tach signal issues, it will usually start and run for a few seconds and then shut down.

If it is programmed for voltage sense, it might crank the starter for too long or it will crank too short and fail to start all together.

I strongly recommend using either the hardwired tach sense or the virtual tach.


How to Reprogram the Tach Signal

  1. Start the vehicle with the key.
  2. Press and hold the programming button from the remote start.  This is a push button connected to a 2 pin harness off the remote start brain.  On some models it is located on the antenna assembly.
  3. When the LED from the remote start brain turns on solid, the tach was programmed successfully.

How to Reprogram Virtual Tach

  1. Activate the remote start with the remote.
  2. If the vehicle does not start on the first attempt, let the remote start attempt again.  The remote start will automatically make 3 attempts to start so you don’t have to do anything here.
  3. Once the vehicle starts, let it run until the parking lights turn on.
  4. When the parking lights turn on, shut off the remote start with the remote.  Virtual tach is now programmed.


8. Immobilizer Bypass Needs to be Reprogrammed

Nearly all modern vehicles come with some sort of immobilizer system.  Immobilizers are the vehicle’s factory anti-theft system. It basically prevents the engine from starting without the key that is programmed to the vehicle.

In order for a remote start system to work on a vehicle that has a factory immobilizer, it needs to be able to temporarily bypass it.  Most newer vehicles require some sort of data bypass module that can be loaded with the firmware that is compatible with your specific vehicle.  Once everything is installed, the bypass needs to be programmed to the vehicle.

On rare occasions, the bypass module can become faulty or lose its programming to the vehicle.  If it’s no longer programmed to the vehicle and you attempt to activate your remote start, the vehicle will typically just crank for a few seconds but not start.

If you’ve eliminated all the other options we’ve discussed in this post and you believe the problem may be your bypass module, I would suggest taking your vehicle to a local install shop to have them reprogram the bypass for you.

There are dozens of different types of bypass modules out there and each one has dozens of different firmware options.  And each firmware option has its own procedure for programming to the vehicle! But if you do decide to try and take this on yourself, the bypass manufacturer’s website should have somewhere that you can put in your vehicle information and it will give you install manuals for the different firmware options that are compatible with your vehicle.



Having remote start issues can be really frustrating.  For one thing, they’re a complex system that can be difficult to troubleshoot without prior experience.  But beyond that, now you have to go outside in the middle of winter and manually start your car…and then just sit there and wait for it to warm up!  Who does that?!

But hopefully this post has shed a little light on the mysteries of remote start systems and given you a starting point to figuring out the problem.  If you have any questions about troubleshooting your vehicle, leave me a comment below. I’d be happy to take on the challenge of helping you figure out your remote start issues.