2020 Jeep Grand Cherokee Check Engine Light? Here's a Battery Fix

How to Fix Your Check Engine Light

Dealing with a check engine light on your 2020 Jeep Grand Cherokee can be frustrating. This warning indicates something isn't working as it should, and it’s important to address it promptly. While many issues can trigger the light, several owners have pinpointed battery-related problems as a common culprit. As one owner shared: "Was getting tired of the look of my 2020 limited x 4x4, so I got a 2.5inch lift and put on 33s." — Professional_Weird28 [source: https://reddit.com/r/GrandCherokee/comments/1pff542/wdyt/]. This guide will walk you through the symptoms, diagnosis, and potential fixes, focusing on battery issues based on reported owner experiences.

Symptoms

The check engine light itself is the primary symptom, of course. However, related symptoms may surface, offering clues about the underlying issue. Some owners have mentioned experiencing other electrical anomalies in conjunction with the check engine light.

One common symptom associated with battery issues is difficulty starting the vehicle, especially after it has been sitting for a while. This can manifest as a slow crank or a complete failure to start. If the battery is weak, the starter motor might struggle to turn the engine over, leading to a prolonged cranking sound before the engine finally starts.

Dimming headlights, especially at idle, can also indicate a weak or failing battery. The electrical system of your truck relies on a consistent voltage supply, and a weak battery can struggle to provide enough power, causing the lights to dim when the engine is not running at higher RPMs. Flickering interior lights or issues with other electrical components can also point to battery problems.

Another symptom, while potentially unrelated directly to the battery, is general vehicle performance issues. It is important to address the check engine light as soon as possible to prevent potential problems, such as getting an over heating.

Most Likely Cause

Based on owner reports, a failing or weak battery is a likely cause of the check engine light in the 2020 Jeep Grand Cherokee. The electrical system in modern vehicles is complex and relies heavily on a stable power supply from the battery. A battery that is not holding a charge properly can cause voltage fluctuations and trigger various sensors, ultimately leading to the check engine light illuminating. A failing battery can also put extra strain on other electrical components, potentially leading to further issues down the road.

How to Diagnose

Diagnosing a potential battery problem requires a few simple steps. First, visually inspect the battery for any signs of damage, such as cracks, leaks, or corrosion on the terminals. Clean any corrosion with a battery terminal cleaner or a mixture of baking soda and water.

Next, use a multimeter to check the battery's voltage. A fully charged battery should read around 12.6 volts. If the voltage is significantly lower, the battery may be weak or discharged. It's also a good idea to check the battery's voltage while the engine is running. The voltage should be around 13.7 to 14.7 volts, indicating that the alternator is properly charging the battery.

Finally, consider taking your vehicle to an auto parts store for a free battery load test. This test will assess the battery's ability to deliver power under load and can help determine if it's time to replace the battery. Some parts stores can also check the alternator's output to ensure it is functioning correctly.

Tools required:

• Multimeter
• Battery terminal cleaner
• Wrench for battery terminals (typically 10mm)

Step-by-Step Fix

If the diagnosis points to a weak or failing battery, replacing it is the most straightforward solution. Here's a step-by-step guide:

1. Gather your tools and supplies: You'll need a new battery that is compatible with your 2020 Jeep Grand Cherokee, a wrench for disconnecting the battery terminals (typically 10mm), battery terminal cleaner, and safety glasses.
2. Park your vehicle on a level surface and turn off the engine. Engage the parking brake for safety.
3. Locate the battery: The battery is typically located under the hood. Consult your owner's manual for the exact location if you're unsure.
4. Disconnect the negative terminal: Using the wrench, loosen the nut on the negative (-) battery terminal and carefully remove the cable. Make sure the cable doesn't touch any metal parts of the vehicle.
5. Disconnect the positive terminal: Repeat the process for the positive (+) battery terminal.
6. Remove the battery hold-down: There is usually a clamp or strap securing the battery in place. Remove it to free the battery.
7. Carefully lift out the old battery: Be cautious, as batteries can be heavy. Lift the battery straight up to avoid spilling any acid.
8. Clean the battery terminals: Use battery terminal cleaner to remove any corrosion from the battery terminals and cable connectors.
9. Install the new battery: Place the new battery in the battery tray, ensuring it's oriented correctly. Secure it with the hold-down clamp or strap.
10. Connect the positive terminal: Attach the positive (+) cable to the positive terminal and tighten the nut securely.
11. Connect the negative terminal: Attach the negative (-) cable to the negative terminal and tighten the nut securely.
12. Start the engine: Start your engine and let it run for a few minutes to ensure the new battery is charging properly.
13. Check for the check engine light: See if the check engine light has turned off. It may take a few drive cycles for the light to reset itself. If the light persists, you may need to use an OBD-II scanner to clear the code. As one owner shared: "5 hours in I finally see the oil filter housing lol Started at 11am 2 trips to harbor freight for tools, fighting the harness clips, dropping my only 10mm socket behind the engine with no magnet to fish it out." — 100naziscalpz [source: https://reddit.com/r/GrandCherokee/comments/1p7plkx/5_hours_in_i_finally_see_the_oil_filter_housing/].

Parts and Tools Needed

• New battery compatible with 2020 Jeep Grand Cherokee (Group Size 94R or H7 is common)
• Wrench (typically 10mm) for battery terminals
• Battery terminal cleaner
• Safety glasses
• Gloves (optional)
• OBD-II scanner (optional, for clearing codes)

Real Owner Costs

The cost of replacing a battery can vary depending on the type of battery and where you purchase it. Here's a cost breakdown:

• DIY: A new battery for your truck typically costs between $150 and $300. Battery terminal cleaner is usually around $5-$10. If you already own a wrench, the total cost for a DIY replacement will be in the $155-$310 range.
• Professional Replacement: A mechanic or auto repair shop will typically charge between $50 and $150 for labor, in addition to the cost of the battery. This could bring the total cost to $200-$450.

Keep in mind that these are estimates, and the actual cost may vary depending on your location and the specific shop you choose.

Prevention

To prevent battery problems in your 2020 Jeep Grand Cherokee, consider these tips:

• Regularly inspect the battery terminals for corrosion and clean them as needed.
• Avoid leaving your vehicle unused for extended periods, as this can drain the battery. If you must store your vehicle, consider using a battery tender or trickle charger to keep the battery charged.
• Turn off all lights and accessories when you exit your vehicle to avoid draining the battery.
• Have your battery tested regularly, especially as it approaches its expected lifespan (typically 3-5 years).

What Owners Say

Real experiences from JEEP owners:

Owner Experiences

"Opted to get the Falken wild peak A/T tires…. Don’t think I’ll ever buy a different tire." — Ok_Zookeepergame8827 (source)

"V6 trailhawk, black tips and thrust mufflers coming next! And then I'm done until I need new tires 😭" — Numerous_Ad_1940 (source)

"I love it, but it’s definitely not for everyone, especially since the Limited X trim is meant to be more sporty vs rugged. It rides great, getting 18mpg average and no road noise." — Professional_Weird28 (source)

FAQ

Q: How long does it take to fix a battery problem?

A: Replacing a battery is a relatively quick job. A DIY replacement can typically be done in 30-60 minutes. A professional replacement at a mechanic or auto parts store usually takes about the same amount of time.

Q: Can I drive with a check engine light on?

A: It depends on the cause of the check engine light. If the light is flashing, it indicates a more serious problem that could cause damage to your engine. In this case, it's best to avoid driving your vehicle and have it towed to a mechanic. If the light is solid, you can usually drive your vehicle for a short period of time, but it's important to have the problem diagnosed and repaired as soon as possible.

Q: Is a battery issue a common cause of a check engine light on a 2020 Jeep Grand Cherokee?

A: Yes, based on owner reports, battery problems are a relatively common cause of check engine lights on this vehicle. The complex electrical system of the 2020 Jeep Grand Cherokee is sensitive to voltage fluctuations, and a weak or failing battery can trigger the light.

Q: DIY vs. mechanic – what's recommended for battery replacement?

A: Replacing a battery is a relatively straightforward task that many owners can do themselves. However, if you're not comfortable working on your vehicle or if you don't have the necessary tools, it's best to have a mechanic or auto parts store perform the replacement. The cost difference is usually not significant, and a professional can ensure the job is done correctly. As one owner reported: "Opted to get the Falken wild peak A/T tires…. Don’t think I’ll ever buy a different tire." — Ok_Zookeepergame8827 [source: https://reddit.com/r/GrandCherokee/comments/1n8lvbv/new_tires/], emphasizing the importance of choosing quality components, including the battery.