FIXED: 2018 jeep wrangler remote start not working

The Short Answer: Why It's Not Working

If your 2018 Jeep Wrangler remote start isn't working, the most likely culprit is a Check Engine Light, a faulty hood latch sensor, or the Auxiliary (ESS) battery is dying. The system is designed to disable remote start if anything looks weird with the vehicle's safety or engine status.

You don't need a mechanic for most of these checks. I'm gonna walk you through exactly how to troubleshoot this yourself, starting with the easy stuff and moving to the tricky electrical gremlins that the 2018 models are kinda famous for.

1. The "Duh" Checklist (Check These First)

Look, I've done this. I've spent an hour tearing my dashboard apart only to realize my door wasn't shut all the way. Before we get into the complex wiring stuff, lets just make sure the computer isn't doing exactly what it's supposed to do.

According to the Jeep owner's manual, the remote start system will abort if:

• The Doors are Open: This includes the rear tailgate. If you have the doors off for the summer, you obviously can't use the factory remote start unless you have defeat clips installed.
• The Hood is Open: Or at least, the Jeep thinks it is (more on that in a minute).
• The Hazard Lights are On: If your flashers are blinking, the car wont start remotely.
• The Transmission isn't in PARK: Pretty self-explanatory.
• Fuel is Low: If that little yellow gas pump light is on, the Jeep saves fuel by refusing to idle remotely.
• Vehicle Speed: The car has to be moving at 0 mph.

If all of those check out, move on to the real issues below.

2. The Notorious Hood Latch Sensor

If I had to bet money on why a 2018 Wrangler JL remote start stopped working, I'd put my money on the hood pin. This is a huge issue with this specific year.

The 2018 Wrangler (specifically the JL body style) has a sensor inside the hood latch mechanism. It tells the computer if the hood is closed. If this sensor gets dirty, corroded, or just misaligned, the Jeep thinks the hood is popped. For safety reasons (so you don't remote start the engine while a mechanic has their hands inside the fan belt), the system disables the start function.

How to test it:

Sit inside the Jeep and turn the ignition to "Run" (don't start the engine, just turn the electronics on). Look at your dashboard cluster. Does it say the hood is open? If the hood is physically latched down but the dash says it's open, you found your problem.

The Fix:

Sometimes you can clean it. Get some electrical contact cleaner and spray it liberally into the latch mechanism near the front grill. Open and close the hood a few times to work it in.

If that doesn't work, you might need to replace the latch. Its a pretty cheap part and takes about 20 minutes to swap out with basic hand tools.

3. The Check Engine Light (CEL)

This is the safety net. If your Jeep's computer (ECU) detects any fault that triggers a Check Engine Light, it automatically kills the remote start feature. This is to prevent the engine from running while there is a potential problem that could damage it.

Note: Sometimes the Check Engine Light hasn't actually turned on yet on the dashboard, but a "pending code" is stored in the computer. This is enough to stop the remote start.

Common CEL causes on the 2018 Wrangler:

• Loose Gas Cap: This is the most annoying one. If you didn't click the gas cap tight enough, it throws an evap leak code. Tighten the cap and drive for a day or two; the light might go out on its own.
• Misfires: Bad spark plugs or coils.
• O2 Sensors: Sensors in the exhaust going bad.

Go to an auto parts store like AutoZone or O'Reillys. They usually scan your codes for free. If you fix the code and clear it, your remote start should come back to life immediately.

4. The Battery Nightmare (Main vs. Aux)

Okay, here is where things get specific to the 2018 model year. If you have the JL Wrangler (the new body style introduced in 2018), you have a dual battery system. It's got the big main battery you can see, and a tiny, annoying Auxiliary battery buried underneath the fuse box.

This secondary battery powers the ESS (Electronic Stop/Start) system-you know, the thing that shuts your engine off at red lights.

Here is the deal: If that little Aux battery starts to die (and they usually only last 3-4 years), it drags down the voltage of the whole system. The Jeep's computer is very sensitive to voltage. If it sees the voltage is even slightly low or unstable, it disables "non-essential" high-load features.

Guess what counts as non-essential? Your remote start.

Symptoms the Aux Battery is the culprit:

• The Auto Stop/Start hasn't been working lately (the engine stays running at red lights).
• You see a "Stop/Start Unavailable" message on the dash.
• The Jeep seems to crank a little slower than usual in the morning.

If you haven't changed your batteries since 2018 or 2019, its almost certainly time. When replacing them, change both batteries at the same time. If you put a new main battery in with a dead Aux battery, the dead Aux battery will drain the life out of your new main one in a month. Trust me on this, don't cheap out here.

5. Your Key Fob Battery is Dead

Sometimes the problem isn't the Jeep, it's the thing in your hand. The 2018 key fob is bulky, and it eats batteries decently fast if you use the features alot.

If you press the remote start button (x2) and the light on the fob doesn't blink, or if you have to stand really close to the Jeep to get the doors to unlock, swap the battery.

The 2018 Wrangler usually takes a CR2450 battery (for the chunky fob) or sometimes a CR2032 if you have the older style. Pop the back cover off with a flathead screwdriver and swap it out. It costs like five bucks.

6. You're in "Valet Mode" or Settings Changed

Did you recently disconnect your battery or get a software update from the dealership? Sometimes the Uconnect system (the touchscreen radio) resets its preferences.

Go into your Uconnect screen:

1. Press Apps or Settings.
2. Find Doors & Locks or Safety & Driving Assistance (menus vary slightly by software version).
3. Look for Remote Start System.
4. Make sure the box is actually checked.

Also, check the "Comfort Systems" setting. This controls if your heated seats and steering wheel come on with the remote start. If this is turned off, the car might be starting, but because the heater isn't blasting, you might think it's not working if you're just judging by the cabin temperature.

7. The "Limp Mode" Logic

This is a bit technical, but good to know. The Jeep has a Transmission Control Module (TCM). If the Jeep detects that the transmission fluid is too hot, or if there is a sensor issue inside the transmission, it disables remote start.

You would usually know this because the car would drive funny (stuck in one gear), but sometimes it's a silent sensor failure. If you have an OBDII scanner, check for transmission codes, not just engine codes.

Specifics: 2018 JK vs. 2018 JL

I mentioned this earlier, but 2018 was a weird year. Jeep sold the old body style (Wrangler JK) and the new body style (Wrangler JL) at the same time.

If you have a JK (The older look, key goes into the steering column ignition):
Your system is much simpler. You don't have the Aux battery issue. For you, it's almost always a hood pin (which is a rubber plunger on the driver side fender) or a check engine light. Also, the JK remote start antenna is located in the soundbar. Sometimes the wire disconnects if you've been messing with the hardtop wiring.

If you have a JL (Push button start):
You have the complex computer systems, the dual batteries, and the sensitive hood latch integrated into the grill. 90% of the advice in this article is geared toward you because the JL is way more finicky.

Aftermarket Remote Starts

Did you buy your Jeep used? It's possible the remote start isn't factory. A lot of 2018 Sports and Saharas didn't come with it, so people added kits like the "Flashlogic" or "Start-X".

If you are pressing the "Lock" button 3 times to start the car (instead of a dedicated "x2" circle button), you have an aftermarket system.

How to fix these:
These systems usually tap into the OBDII port or the ignition harness. They often "lose" their programming if the car battery dies. You usually have to re-pair them.

• Find the module (usually zip-tied under the steering wheel dash).
• Look up the brand name printed on the box.
• Google "[Brand Name] re-programming guide".

Usually, it involves holding a button on the box while turning the ignition on, but it varies by brand.

Resetting the System (The "Turn it off and on again" fix)

If you have checked the doors, hood, gas cap, and batteries, and it still wont work, try a hard reset. Computers get confused sometimes. Static electricity builds up, or a logic gate gets stuck.

1. Pop the hood.
2. Take a 10mm wrench and disconnect the Negative (Black) battery terminal.
3. Isolate the cable so it doesn't touch metal.
4. Wait about 15 to 30 minutes. This drains the capacitors in the modules.
5. Reconnect the cable and tighten it down.

Warning: On the JL, this might reset your radio presets and your compass might need to be recalibrated (just drive in a circle a few times in a parking lot, it fixes itself). But this often clears temporary "glitches" in the remote start module.

When to see the Dealer

I hate going to the dealership as much as you do. But there are two scenarios where you kinda have to.

1. RF Hub Module Failure:
There is a module in the back of the Jeep called the RF Hub. It receives the signal from your key. In some early 2018 JLs, these units were defective or prone to water damage if the rear window leaked. If this module is dead, no amount of battery swapping will fix it. The dealer has to replace it and program it to your VIN.

2. Software Updates:
Jeep releases TSBs (Technical Service Bulletins) constantly. There have been updates for the 2018 Wrangler regarding the Body Control Module (BCM) that fix "intermittent remote start failure." If your software is old, only the dealer tools (WiTech) can update it.

Summary

Don't panic. 9 times out of 10, your remote start isn't broken-it's just disabled because of a safety sensor. Start with the hood latch. If that looks good, scan for engine codes. And if you are still on the original factory batteries from 2018, do yourself a favor and replace them before winter hits anyway.

Good luck getting it fired up!

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Frequently Asked Questions

Does the 2018 Jeep Wrangler have a remote start reset button?

No, there isn't a dedicated physical button to reset just the remote start. The best way to "reset" the system is to disconnect the vehicle's negative battery terminal for 15 minutes to clear the computer modules.

Why does my Jeep horn honk but not start remotely?

If the horn honks once (or twice depending on settings) but the engine doesn't crank, the Jeep received the signal but rejected the request. This confirms your key fob is working, but a safety parameter (like an open hood, low fuel, or Check Engine Light) is preventing the start.

Can I disable the Auto Stop/Start to fix my remote start?

Simply pushing the "A" button on the dash to turn off Stop/Start won't fix the remote start if the Aux battery is already dead. The remote start system checks the voltage of the battery, not the position of the switch. You have to replace the bad battery to resolve the issue.

How long will the Jeep run on remote start before shutting off?

The 2018 Wrangler will run for 15 minutes. You can extend it one time by pressing the remote start button twice again, giving you a total of 30 minutes. After that, you must physically enter the vehicle and turn the ignition on.

Will remote start work if my top is off?

Yes, but only if the doors are connected and closed. If you have removed the doors, the "Door Ajar" circuit is open, preventing remote start. You can buy "door defeat" clips or springs that hold the door pin button in, tricking the Jeep into thinking the doors are on and closed.