2021 Jeep Grand Cherokee Has A Check Engine Light

Resolve Check Engine Light Issues in 2021 Jeep Grand Cherokee

Find Repair Location
Reviewed by
Devin Cabugcal
Written by RepairPal Car Genius
Updated January 14, 2025
0%
40% chance it's the
Emissions System
0%
60% chance it's
Something else
The most common reasons a 2021 Jeep Grand Cherokee has a check engine light are an emissions system component, a sensor, or a catalytic converter.
  • Emissions System: A faulty emissions system component, such as an oxygen sensor or EGR valve, can lead to increased emissions and trigger the check engine light.
Proper diagnosis will determine the exact cause of your symptom, saving you money on unnecessary repairs. The diagnostic experts at RepairPal Certified shops have the right tools and experience to solve any symptom.

How much does it cost to fix a 2021 Jeep Grand Cherokee has a check engine light?

Common Repairs

The total repair cost will vary based on the condition of your vehicle and the number of repairs needed to fix your symptom. Proper diagnosis will save you money by finding the exact repairs needed to fix your car right the first time.

A faulty oxygen sensor is one of the most common causes of a check engine light. Symptoms may include a decrease in fuel mileage, hesitation or misfiring from the engine, rough idling or even stalling. A faulty sensor may cause the vehicle to fail an emissions test.

Any time there is an emissions fault the check engine light will be displayed. The purpose of the check engine light is to inform the driver that an emission related fault has been found, and that there are on-board diagnostic (OBD) trouble codes stored in the powertrain or engine control module. Additionally, since the emissions systems are so intertwined into engine control and transmission control systems, symptoms may include nearly any sort of drivability concerns. This may include harsh shifting, failure to shift, hesitation on acceleration, jerking, engine failure to start or run, loss of power, or any number of other drivability issues.

Due to the nature of electrical systems on modern vehicles, the range of problems these can cause are nearly limitless. However, there is a way to categorize them in two ways. Permanent and intermittent problems. Permanent problems appear and remain. This may be the vehicle will not start, the radio does not work, or the door chime will not turn off among many, many others. These problems are more straight-forward to diagnose since they present themselves at all time. This means there will always be a fault to find. Intermittent electrical problems, however, can be difficult or impossible to locate, since they appear then disappear without warning. The best case scenario for an intermittent issue is when replicating the problem is easily accomplished and understood. This allows a technician to make an issue semi-permanent, allowing them to find the fault. Other issues that come and go without warning and cannot be replicated on demand must occur when the technician is servicing the vehicle, otherwise there is no problem to correct. It is most important to understand that electrical system faults always require inspection, and can include the vehicle working in any manner, or not working at all.

Like we noted in the last section, general diagnosis symptoms are the most vague of the bunch. There are several diagnostic spectrums, electrical diagnosis, drivability diagnostics, engine diagnostics, transmission diagnostics, and the list could continue for about 5 or 10 more spectrums of diagnostics. The most important take-away here, is that general diagnostics are diagnostics that have no other spectrum in which they fit, or the problem is unknown. This means that any vehicle left outside of a repair facility with the keys and an authorization to perform diagnosis will be diagnosed under the general diagnosis spectrum.

When the Check Engine Light comes on, you may experience engine performance issues such as poor acceleration, rough idling, or an engine that won't start. In some cases, no abnormal symptoms will be experienced. Other systems like the transmission or ABS can cause the Check Engine Light to illuminate and lights for those systems can come on at the same time. Similar lights may say "Check Engine Soon", "Malfunction Indicator Light" or just "Check". In rare case the engine can overheat.

What are the initial diagnostic steps to take for a check engine light on a 2021 Jeep Grand Cherokee?

When faced with a check engine light on your 2021 Jeep Grand Cherokee, it's essential to adopt a systematic diagnostic approach. Start by checking the gas cap, as a loose or damaged cap is a common and easily fixable issue that can trigger the light. Next, take a moment to inspect your dashboard gauges for any additional warning lights or unusual readings, which may offer further insights into the problem. Utilizing an OBD-II scanner is a crucial step; it allows you to retrieve specific trouble codes from your vehicle's computer, providing a clearer picture of the underlying issue. Additionally, visually inspect the wiring and connections under the hood for any signs of damage or looseness, as these can also lead to the check engine light being activated. Finally, pay attention to your vehicle's performance—any unusual noises, vibrations, or handling changes can be significant indicators of what might be wrong. By following these steps, you can effectively narrow down the cause of the check engine light and take appropriate action.

What are the common problems that could cause the check engine light to illuminate in a 2021 Jeep Grand Cherokee?

When the check engine light comes on in a 2021 Jeep Grand Cherokee, it can signal a range of common issues that are often manageable for DIY enthusiasts. One of the simplest problems to check is a loose gas cap, which can easily be tightened or replaced if damaged. Another frequent culprit is a faulty oxygen sensor, which can affect fuel efficiency and emissions; this may require a replacement if diagnosed. Additionally, issues with the catalytic converter can lead to significant performance problems, and while this may be more complex to address, understanding its role can help in troubleshooting. Worn spark plugs are also a common issue that can cause the check engine light to illuminate, and replacing them is a straightforward task for those with basic mechanical skills. Furthermore, a malfunctioning mass airflow sensor or ignition coil can trigger the light, both of which can be tested and replaced with relative ease. Lastly, an engine misfire, often caused by bad spark plugs or fuel injectors, can also activate the warning light, indicating a need for further inspection. By being aware of these potential issues, DIYers can take proactive steps to diagnose and resolve the problems, ensuring their Jeep Grand Cherokee runs smoothly.

How urgent is it to address the check engine light in a 2021 Jeep Grand Cherokee?

Addressing the check engine light in a 2021 Jeep Grand Cherokee is crucial for maintaining the vehicle's performance and safety. This warning light can indicate a range of issues, from minor sensor malfunctions to serious engine problems that could compromise your vehicle's reliability. Ignoring the check engine light can lead to more severe damage, resulting in costly repairs and potentially leaving you stranded. For DIY enthusiasts, it’s essential to recognize that some issues, like engine misfires or overheating, require immediate attention to prevent further complications. By promptly diagnosing and resolving the underlying problems indicated by the check engine light, you not only enhance your vehicle's fuel efficiency but also ensure a safer driving experience. Therefore, taking action as soon as the light illuminates is not just advisable; it is a necessary step in responsible vehicle maintenance.

You’ve got options with RepairPal

Whether you need a more accurate auto repair estimate or help finding a reputable shop in your area, we’ve got you covered.