Will Remote Start Work With Check Engine Light On

The Short Answer: Probably Not

If you're in a rush, here is the deal: If your Check Engine Light is on, your factory-installed remote start is almost 100% guaranteed not to work. It doesn't matter if you drive a Ford, a Chevy, a Honda or a Toyota. The manufacturers program the cars this way on purpose.

When you hit that button on your key fob, the car runs a quick system check. If it sees an active "trouble code" (which is what triggers the light), it aborts the start sequence immediately. You might see your parking lights flash once or hear a quick honk, but the engine won't turn over.

It’s super annoying especially when it's freezing outside, but the car is actually trying to save itself.

Why Does the Car Do This?

It feels like the car is punishing you, but it’s actually a safety feature. Here is the logic behind it.

When you are driving the car yourself, you have eyes on the gauges. If the engine starts overheating, making a weird noise, or smoking, you can pull over and shut it off. But when you remote start a vehicle, there is nobody in the driver's seat to monitor those vital signs.

The car's computer (the ECU) doesn't really know if the Check Engine Light is on because of something minor like a gas cap or something major like a misfiring cylinder or low oil pressure. To be safe, it assumes the worst.

If the computer allowed the engine to run for 10 or 15 minutes unattended with a major mechanical issue, you could walk out to a seized engine or even a fire. So, the engineers basically said, "If the car is sick, it stays asleep until a human is present."

Factory vs. Aftermarket Remote Starters

There is a big difference here depending on what kind of system you have installed.

Factory Systems (OEM)

As mentioned before, these are tied directly into the car's brain. If the dashboard is lit up like a Christmas tree, the remote start is dead in the water. This is true for pretty much every modern vehicle made after 2010.

Aftermarket Systems

If you went to a car audio shop and had a system like a Viper, Compustar, or Python installed, you might have a different experience. These systems often bypass the car’s main logic board to crank the starter manually.

While newer aftermarket systems are getting smarter and reading data from the car's computer (CAN bus), older or simpler setups might not care about the Check Engine Light. They just send a signal to the starter motor to go. So, if you have an aftermarket unit, it might still start the car.

Warning: Just because you can force it to start doesn't mean you should. If that light is blinking, running the engine without you sitting in it is a gamble.

The Most Annoying Reason: The Loose Gas Cap

You wouldn't believe how often this happens. I’ve had friends panic because their brand new truck wouldn't remote start, thinking the transmission was blown or something crazy.

In reality? They just filled up on gas and didn't click the cap until it was tight.

Here’s why this matters: Your car has an EVAP system that catches fuel vapors so they don't pollute the air. It’s a sealed system. If the gas cap is loose, the system detects a "leak." This triggers a Check Engine Light code (usually P0440, P0442, or P0455). And boom, your remote start is disabled.

The Fix: Tighten the cap until it clicks. Note that the light won't go off immediately. You usually have to drive the car for a few cycles (driving for maybe 50 miles or starting and stopping the car a few times) before the computer realizes the leak is fixed and turns the light off.

How Different Manufacturers Handle It

While the general rule is "no go," it helps to know specifically what your car brand does. According to owner's manuals and mechanic forums, here is how the big guys handle it:

• Ford / Lincoln: Ford is very strict about this. If the Malfunction Indicator Light (MIL) is on, remote start is disabled. You might see a message on your dash cluster saying "Remote Start Disabled."
• General Motors (Chevy, GMC, Cadillac): Same deal. GM vehicles will usually flash the lights but refuse to crank if there is a current stored code.
• Toyota / Lexus: Toyota is famous for disabling fun stuff when safety is a concern. The CEL will definitely kill the remote start function.
• Honda / Acura: Honda systems check for any "powertrain" codes. If one exists, the car stays off.
• Subaru: Subaru creates a whole "Christmas tree" effect. Usually, if the CEL comes on, it also disables your Cruise Control, X-Mode, and yes, your Remote Start.
• Jeep / Dodge / Ram: These will usually run for about 10 seconds and then shut off, or just not start at all. The driver information screen usually tells you "Remote Start Aborted - Check Engine."

Troubleshooting Steps: How to Get Your Remote Start Back

So, your light is on and you want your warm car back. Here is what you need to do, step by step.

1. Check the Obvious Stuff

Go tighten that gas cap. Even if you think you did it right, go give it another crank. Also, check that your hood is fully closed. Most cars have a "hood pin" safety switch that disables remote start if the hood is popped (so the engine doesn't start while a mechanic has their hands inside).

2. Read the Code

You need to know why the light is on. You don't need to be a mechanic to do this.

• Buy a scanner: You can get a cheap OBDII scanner on Amazon for like $20. It plugs into the port under your steering wheel.
• Go to an auto parts store: Places like AutoZone, O'Reilly's, or Advance Auto Parts will almost always scan your car for free. They'll give you a printout of the error code.

3. Assessing the Damage

Once you have the code, Google it.
If it’s something minor (like an EVAP leak or an O2 sensor heater circuit), you know the car isn't going to explode. If it’s something scary like "Cylinder Misfire" or "Low Oil Pressure," do not try to bypass the system. You need to fix that asap.

4. Clearing the Code

This is the "cheat" way to get remote start back temporarily. If you have a scanner, you can hit the "Erase Codes" or "Clear DTC" button. This will turn off the Check Engine Light.

Heads up though: This doesn't fix the car. It just deletes the memory of the problem. If the problem is real (like a bad sensor), the light will pop back on after you drive for 20 minutes, and your remote start will stop working again. But, it might get you through a cold morning until you can get to the shop.

Other Reasons Remote Start Might Fail

If you check your dashboard and there is NO Check Engine Light, but the remote start still isn't working, it could be something else. The computer is picky. Here are other reasons it says no:

• Low Fuel: Many newer cars won't remote start if the "Low Fuel" light is on. They don't want to burn the last of your gas while idling in the driveway.
• Battery Voltage: If your car battery is old or weak, the system might disable remote features to save enough juice to start the car when you actually get in.
• Key Fob Battery: Sometimes the car is fine, but your remote battery is dying and sending a weak signal.
• Door/Hood Open: If a door switch is broken and thinks a door is open, it won't start.
• Hazard Lights: Believe it or not, some cars won't remote start if the hazard flashers are on.

Is It Expensive to Fix?

This is the question everyone dreads. It honestly depends on what threw the code. If it’s the gas cap, it's free (or $15 for a new cap). If it’s an Oxygen Sensor (O2 sensor), you might be looking at $150 to $300. If it is a Catalytic Converter issue, that gets pricey.

But remember, you aren't paying to fix the remote start. You are paying to fix the engine issue. Getting the remote start back is just a bonus.

Summary

Look, I know it sucks. Walking out to a cold car in the middle of January because a tiny orange light is on the dash is frustrating. But the system is designed to protect your investment.

If that light is on, don't ignore it just because you want the convenience. It’s your car’s way of asking for help. Get the code scanned, check the gas cap, and get the issue resolved. Once the computer is happy and the light is off, you’ll be back to enjoying a warm seat and a defrosted windshield.

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Frequently Asked Questions

Can I just disconnect the battery to clear the light?

You used to be able to do this on old cars. On modern cars (anything with a screen in the dash), I wouldn't recommend it. Disconnecting the battery resets your radio presets, your clock, and sometimes even the transmission learning patterns. It’s annoying. Just use a cheap OBDII scanner to clear the code instead.

Does a Tire Pressure light (TPMS) stop remote start?

Usually, no. The TPMS light (the little exclamation point inside a horseshoe shape) is considered a safety warning, but not an engine health warning. Most Fords, Chevys, and Toyotas will still let you remote start with a low tire. However, some very strict safety packages might disable it.

Will the Check Engine Light clear itself?

Yes, but only if the problem is actually fixed. If it was a loose gas cap and you tightened it, the light will eventually go off on its own after a few days of driving. If the part is actually broken, the light will stay on forever until you replace the part.

My remote start flashes the lights but doesn't start. Is that the CEL?

It's very likely. Most systems use the parking lights to communicate error codes. For example, on some systems, 4 flashes means "Remote Start Disabled due to Check Engine Light." Check your owner's manual for the flash codes.

Can a mechanic bypass the sensor so remote start works anyway?

Technically, a shady mechanic could rig something up, but no reputable shop will do this. It’s a huge liability. If they bypass a safety sensor and your engine melts down while idling in your driveway, that's on them. Don't ask them to do this.