When your Jeep Grand Cherokee remote start decides not to work, it can be a frustrating experience, especially on a cold morning or a hot afternoon. You expect that button push to fire up your engine, warm or cool the cabin, and make your life a little easier.
Instead, you're met with silence, or worse, an error message. This isn't just an inconvenience; it can feel like a significant problem with your vehicle.
The good news is that a non-working remote start system on a Jeep Grand Cherokee is often fixable, and many of the common issues can be diagnosed and resolved by the owner with a little patience and know-how. Before you rush to the dealership, understanding the potential culprits can save you time and money.
From simple battery issues to more complex electronic glitches, there’s a range of possibilities. This guide will walk you through the common reasons why your Jeep Grand Cherokee’s remote start might not be working and what you can do to get it back up and running.
Common Reasons For Remote Start Failure
Several factors can prevent your Jeep Grand Cherokee’s remote start system from functioning correctly. These issues range from simple user errors to more complex mechanical or electrical problems.
Understanding these common causes is the first step toward troubleshooting.
Key Fob Battery Issues
One of the most frequent and easiest-to-fix reasons for a remote start not working is a dead or weak key fob battery. The remote start system relies on a strong signal from your key fob to communicate with the vehicle. If the battery is low, the signal might not be strong enough to reach the car, or it might be too weak to trigger the remote start function.
- Symptoms: You might notice that other functions of your key fob, like unlocking or locking doors, are also becoming sluggish or require you to be closer to the vehicle. Sometimes, the remote start button might not even light up or give any indication that it’s being pressed.
- Troubleshooting: The first thing to try is replacing the battery in your key fob. Most Jeep Grand Cherokee fobs use a common coin-cell battery, usually a CR2032. You can find these batteries at most grocery stores, drugstores, or electronics shops. To replace it, you typically need to carefully pry open the key fob casing, often with a small flathead screwdriver or a plastic trim tool. Be gentle to avoid damaging the fob. Once the old battery is out, note its orientation (positive (+) and negative (-) sides) and insert the new one in the same way. Test the remote start again.
- Pro Tip: Keep a spare key fob battery in your glove compartment. This way, if your primary fob dies unexpectedly, you can quickly swap it out and get your remote start working again without a trip to the store.
Vehicle Battery And Power Concerns
Your Jeep Grand Cherokee’s 12-volt battery is the heart of its electrical system. If this battery is low on charge or failing, it can cause a cascade of electrical issues, including the remote start system malfunctioning. The remote start system requires a certain voltage to operate safely and effectively. If the vehicle’s battery voltage drops too low, the system may be disabled to prevent the car from failing to start after the remote start sequence.
- Symptoms: Besides the remote start not working, you might notice other signs of a weak vehicle battery. These include slow engine cranking, dim headlights, dashboard warning lights (like the battery or check engine light), and other electrical components acting erratically.
- Troubleshooting: Check your vehicle’s battery voltage if you have a multimeter. A healthy battery should read around 12.6 volts when the engine is off. If it’s significantly lower, it might need charging or replacing. If you suspect a battery issue, try jump-starting your Jeep or charging the battery. If the remote start works after the battery has been charged or replaced, you’ve found your culprit.
- Important Note: A weak vehicle battery can also be a sign of a larger charging system problem, such as a failing alternator. If you repeatedly have battery issues, have your charging system checked by a qualified mechanic.
Door Ajar Or Hood Open Issues
For safety reasons, the remote start system on your Jeep Grand Cherokee is designed to prevent activation if any of the vehicle’s doors, the trunk, or the hood are not securely closed. This is a critical safety feature. If a sensor for any of these entry points is faulty or if something is preventing a door or the hood from closing completely, the remote start system will not engage.
- Symptoms: The remote start button on your fob might flash a specific pattern, or the vehicle might not respond at all. You might also see a warning light on your dashboard indicating that a door or the liftgate is open, even if you believe everything is closed.
- Troubleshooting: Visually inspect all doors, the trunk, and the hood to ensure they are fully latched. Sometimes, a small obstruction, like a floor mat or a piece of cargo, can prevent a door from closing completely. Check that the door ajar sensors are not stuck. These sensors are usually small buttons or switches located on the door frame or the door itself. You can try pressing them in and releasing them a few times to ensure they are functioning correctly. If you have a liftgate, ensure the mechanism is clear of debris.
- When to Seek Help: If you’ve confirmed everything is closed and latched, but the dashboard still indicates an open door or the remote start won’t work, there might be a faulty sensor or a wiring issue. This would require professional diagnosis.
Fuel Level And Other Vehicle Status Requirements
Modern vehicles, including the Jeep Grand Cherokee, have sophisticated vehicle status requirements that must be met before the remote start system will engage. These are in place to ensure the vehicle can start and run safely without issue.
- Low Fuel Level: Most remote start systems will not activate if the fuel tank is below a certain level (often around 1/4 tank). This is to prevent the vehicle from starting and then running out of fuel, potentially leaving you stranded.
- Check Engine Light: If your Check Engine Light (CEL) is illuminated, the remote start system will likely be disabled. The CEL indicates a detected fault in the engine or emissions system, and the vehicle’s computer prioritizes addressing this issue before allowing convenience features like remote start to operate.
- Service Required Indicators: Other service indicators or warnings, such as low oil pressure or transmission faults, can also prevent remote start activation.
- Troubleshooting:
- Fuel: Ensure your fuel tank is at least a quarter full. If it’s low, fill it up and try the remote start again.
- Check Engine Light: If the CEL is on, you must diagnose and repair the underlying issue causing the light to illuminate. This might involve reading diagnostic trouble codes (DTCs) with an OBD-II scanner. Once the fault is fixed and the light is off, the remote start should function again.
- Other Warnings: Address any other active warning lights or service messages on your dashboard.
Key Fob Programming And Synchronization Issues
Over time, or after a battery change, your key fob might lose its programming or synchronization with your Jeep Grand Cherokee. The vehicle needs to recognize the specific signal from your fob to allow it to start the engine.
- Symptoms: The remote start might work intermittently, or not at all, even with a new battery. Other key fob functions might also be affected.
- Troubleshooting: Many Jeep Grand Cherokees have a key fob relearning procedure that you can perform yourself. This usually involves a specific sequence of turning the ignition on and off and pressing buttons on the fob. Consult your owner’s manual for the exact procedure for your model year. If the self-relearn process doesn’t work, or if you’re uncomfortable performing it, a dealership or a qualified automotive locksmith can reprogram your key fob.
- Lost Keys: If you’ve lost a key fob, it’s crucial to have the lost fob deleted from the vehicle’s system to prevent theft. This is a task that requires specialized equipment and is best handled by a professional.
Advanced Troubleshooting Steps
If the basic checks haven’t resolved your Jeep Grand Cherokee’s remote start issues, it’s time to look at more complex possibilities that might require a deeper dive or professional assistance.
Remote Start Module Or System Faults
The remote start system itself is controlled by a dedicated module, often integrated into the vehicle’s Body Control Module (BCM) or a separate module. If this module malfunctions, it can cause the entire system to fail.
- Symptoms: The remote start may not respond at all, or it might engage but then shut off unexpectedly. Sometimes, other electronic features might also be affected if the BCM is involved. Error codes related to the remote start module might be present.
- Troubleshooting: Diagnosing a faulty module often requires specialized diagnostic tools that can communicate with the vehicle’s various electronic control units (ECUs). A technician can scan for Diagnostic Trouble Codes (DTCs) specific to the remote start system. If a DTC points to the module itself, it may need to be repaired or replaced. This is typically a job for a dealership or an experienced automotive electronics specialist.
- Fuse Check: While less common for complete failure, it’s worth checking the fuses related to the remote start system. Consult your owner’s manual for the fuse box locations and the specific fuse numbers associated with the remote start or ignition system. A blown fuse can indicate an underlying electrical short or overload.
Aftermarket Alarm Or Remote Start System Issues
If your Jeep Grand Cherokee has an aftermarket alarm or remote start system installed, the factory remote start might be disabled or may not function correctly. Aftermarket systems can sometimes interfere with the vehicle’s factory electronics.
- Symptoms: The factory remote start button might do nothing, or the aftermarket system might be the only one that functions (or neither works). You might notice other electrical oddities.
- Troubleshooting: If you have an aftermarket system, try to identify its brand and model. Look for any visible control modules or key fobs associated with it. The installation manual or the manufacturer’s website might provide troubleshooting steps for their system. Sometimes, the aftermarket system might have a bypass mode or a specific procedure to enable/disable the factory remote start.
- Professional Disconnection: If the aftermarket system is suspected of causing the problem, the safest approach is to have it professionally removed or diagnosed. Improper removal can lead to further electrical issues. A reputable car audio or alarm installer can help.
Software Glitches And Updates
Modern vehicles rely heavily on software. Like any computer, the vehicle’s software can sometimes experience glitches that affect various functions, including the remote start system.
- Symptoms: The remote start might work sporadically or fail without a clear mechanical reason. The issue might appear after a recent service or electrical event.
- Troubleshooting: Jeep dealerships have access to the latest software updates and diagnostic tools for their vehicles. If a software glitch is suspected, they can check if there are any available recalls or Technical Service Bulletins (TSBs) related to the remote start system or the BCM. Applying the latest software update can often resolve these types of issues.
- Importance of Dealer Diagnostics: This is one area where dealership expertise is often necessary, as they have the specific tools and software required to diagnose and update vehicle modules.
Antenna Or Signal Reception Problems
The remote start system uses radio frequencies to communicate between the key fob and the vehicle. Issues with the antenna or signal reception can lead to intermittent or complete failure.
- Symptoms: The remote start only works when you are very close to the vehicle, or it fails to respond even from a normal distance.
- Troubleshooting: Ensure there are no obstructions between the key fob and the vehicle. Things like large metal objects, other vehicles, or even dense buildings can interfere with the signal. Check the vehicle’s antenna location (often integrated into the windshield or body panels) for any visible damage. If you suspect an antenna issue, it would require professional inspection.
Specific Jeep Grand Cherokee Model Year Considerations
Different model years of the Jeep Grand Cherokee might have unique quirks or common issues related to their remote start systems. While the general troubleshooting steps apply broadly, specific design changes or known problems can affect certain generations.
Early Generations (e.g., Wj, Wk)
Older models of the Grand Cherokee might have more mechanical or simpler electronic systems. Issues could stem from worn-out components, corrosion in electrical connectors, or less sophisticated diagnostic capabilities.
- Common Issues: Key fob battery degradation, door lock actuator failures affecting door-ajar sensors, and older wiring harness issues were more prevalent. The remote start module might be a separate, identifiable component.
- Troubleshooting Focus: Thoroughly check all physical switches and sensors. Inspect wiring harnesses for damage or corrosion, especially in areas exposed to moisture. Battery testing and replacement are always the first steps.
Later Generations (e.g., Wk2, Wl)
Modern Jeep Grand Cherokees feature highly integrated electronic systems, often relying on the Body Control Module (BCM) for remote start functions. This means software and module integrity become more critical.
- Common Issues: Software glitches, BCM communication errors, and issues with the integrated keyless entry and start systems are more likely. Aftermarket installations can also cause more complex interference.
- Troubleshooting Focus: Software updates and module diagnostics are key. Pay close attention to dashboard warning lights, as they often provide clues to underlying electronic faults. Always ensure the vehicle’s battery is in excellent condition, as low voltage can cause unpredictable electronic behavior.
Mopar Remote Start Kits
Some Grand Cherokees may have had the remote start system installed as a Mopar accessory kit after the vehicle was purchased. These kits have their own specific components and installation procedures.
- Common Issues: Improper installation, loose connections, or interference with the vehicle’s existing wiring can cause problems. The kit’s specific control module or antenna might fail.
- Troubleshooting Focus: If you have a Mopar kit, referencing the installation manual can be helpful. Look for any specific indicators or error codes associated with the kit itself. If the kit was installed by a dealer, they are best equipped to service it. If installed elsewhere, consult the installer.
Maintaining Your Remote Start System
Preventative measures can significantly reduce the likelihood of your Jeep Grand Cherokee’s remote start system failing. Regular maintenance and awareness can keep this convenient feature working reliably.
Regular Key Fob Battery Replacement
As mentioned earlier, the key fob battery is a consumable item. Don’t wait for it to die completely.
- Recommendation: Replace your key fob battery once a year, or whenever you notice any sluggishness in its response. This is a cheap and easy way to prevent remote start failures
