Did your trusted Jeep Wrangler start having sporadic ignition issues? Or have you experienced that it won’t start at all even when it has power? You’re not alone. Many owners, especially of the 2018 model, have encountered this disappointing problem after switching off their engines at a gas station.
In some cases, the engine can turn over but won’t start at all, even though the battery can still power the other electronics. This can be quite scary for first-time Jeep owners, and most of them end up taking their Jeeps to a mechanic, which can cost them quite a lot.
So, before you take yours to an expert, you should find out the cause of the problem. Luckily, troubleshooting Jeeps is quite easy, thanks to their huge engine compartment.
So if your Jeep Wrangler won’t start but has power and you want to know how to troubleshoot it, please read on.
Why Won’t My Jeep Wrangler Start?
If not well-maintained, Jeeps can encounter lots of mechanical or electrical issues that will prevent them from starting. In most cases, the issue is caused by low battery power. Luckily, jump-starting the Jeep provides a quick fix for this.
But what would you do if your Jeep won’t start even with a fully-charged battery?
Here are some of the possible reasons why your Jeep Wrangler won’t start, even if it seems that you have turned your engine over:
No vehicle can start with little to no fuel. In most cases, the battery will be able to turn the engine over, but not start the vehicle due to the lack of fuel in the fuel injector. In some cases where the fuel tank may be full, a spoiled fuel injector may disrupt the flow of fuel in the Jeep, preventing it from starting after the engine turns.
The starter is a unique component whose main work is turning the Jeep’s engine over and letting all the other things happen. When you turn the key in the ignition, it engages the starter, which turns your engine over, making it possible for the Jeep to start. If the starter has issues, it won’t turn over the Jeep’s engine and start the car.
Corroded Battery Terminals
Another issue that can hinder the flow of power in the Jeep is corroded or dirty battery terminals. Remember, the terminals can get corroded when exposed to moisture. And when this happens, starting your Jeep can be quite challenging.
Some Jeeps may have faulty ignition that ends up overworking the starter and even damaging it. In fact, most Jeep owners have complained that their keys got stuck at some point. This resulted in the starter being engaged constantly until it burns out.
If you don’t know the sound it produces when starting, then you might not be able to detect this issue. But if you notice the clicking sound, then you may need to replace the ignition.
There are numerous things that can prevent a Jeep Wrangler from starting. These include loose wirings and connections that can affect the flow of power in the car from the battery, an overheated transmission switch, or damaged spark plugs. Even when your battery is fully charged, these factors can also prevent your Jeep from starting.
How to Troubleshoot a Jeep Wrangler That Won’t Start But Has Power
Step 1: Confirm the Condition of the Battery
The first thing you should do is confirm the voltage level of the battery and its terminals. A fully-charged battery should give a reading of about 12.6 volts, so if your battery is less than 25% charged, then it can’t start the engine.
Next, inspect its terminals for any sign of rust or dirt. Remember, dirt and rust can hinder the flow of power from the battery to the other parts of the Jeep.
If they are corroded, you can spray some WD40 on the terminals to help loosen the rust. Simply spray the WD40 on the terminals and leave it there for a few minutes before cleaning them using a paper towel.
If the battery’s terminals are dirty, you can unscrew the terminals and clean them with a paper towel. After removing the rust and dirt, you can reconnect the terminals. But if the terminals are too far gone, then you should replace them.
Step 2: Examine the Connecting Cables from the Battery to the Engine
The reason why your Jeep won’t start may be a loose cable, so examine all the cables connecting the battery to the engine. If you notice any loose wire, secure its connection before trying to start the Jeep. If the battery is fully charged and your Jeep still doesn’t start, you should proceed to test the starter.
Step 3: Test the Starter
After determining that neither the battery’s terminals nor the cables are not the issue, you should locate the starter.
Normally, the function of the starter is to crank or turn the engine. So if the engine turns, then the issue lies in another part of the Jeep. If you love off-roading, then chances are that your Jeep’s starter has been exposed to dust and moisture. This can reduce its lifespan and even make it difficult for the starter to crank the engine.
To test the starter, you need to first locate it by following the battery’s red wires. Once you have located it, you will notice its two poles sticking out. Next, form a connection by placing the screwdriver across the two poles. But make sure your hand doesn’t touch the metallic part of the screwdriver.
After creating the connection, you can listen to the starter and find out if it’s running. If the Jeep’s starter is running, it’s still fine; otherwise, you will need a replacement. After replacing it, ensure that all the wires linking the starter to the engine and the battery are in good condition.
Step 4: Confirm If the Ground Strap Is Loose
After confirming that the starter is working, you can check if the ground strap is in working condition. The ground cable is the huge black wire connecting the battery’s negative terminal to the chassis. In fact, all the Jeep’s electrical currents must go through the ground strap.
If the ground strap is loose, then you may have some serious electrical issues, including the Jeep not starting. You will need to replace the ground strap if the issue is ground-related. Some Jeeps are known for having inadequate grounding, so you may even have to install a second cable.
To test the ground strap, you will need a voltmeter. Simply attach the voltmeter’s positive prong to the battery’s positive terminal and the negative on the outer part of the starter. But make sure the surface of the starter is clean and has no oil or grease. If the reading you get is equal to the reading you get when the battery is at rest, then the ground earth cable is okay.
Finally, you can try starting the Jeep and find out if it works. If it doesn’t start then, you can check the fuel level and fuel pump.
Step 5: Check the Fuel Level and Fuel Pump
In some cases, this issue may be fuel-related. In such scenarios, the first thing you should do is confirm if the fuel is being supplied from the tank all the way to the Jeep Wrangler’s injectors. If your Jeep has been losing power while towing a load or driving uphill, then it’s possible that the fuel pump is damaged.
Once the fuel pump gets damaged, the Jeep won’t start since the fuel doesn’t reach the engine. If this is the case, you should replace it before starting your Jeep. If it still doesn’t work after the replacement, then proceed with checking the spark plugs.
Step 6: Check the Condition of the Spark Plugs
If the pump delivers more than enough fuel to the injectors and yet the problem persists, then the issue may be with the spark plugs. The spark plugs are the most crucial part of the engine as they serve as the bridge for electricity. When electricity crosses this bridge, it ignites the Jeep’s sparks, creating a gas vapor that starts the engine. Therefore, it’s crucial that you replace the plugs in time.
So, you can try and replace the spark plugs, and if everything is working perfectly, then the Jeep should start. But if it still doesn’t start, then the issue could be with the alternator. If so, you need to take it to an expert for a replacement.
Why Is This Problem Common With the 2018 Jeep Wranglers?
Most 2018 Jeep Wrangler owners have reported this issue. In fact, some of them claim that they were left with a non-starting Jeep after switching their engines off for a bit. And since the battery has power, the radio and the headlights are always working—it’s just that the Jeep won’t start. Fortunately, the Jeep always responds after an hour.
In this case, the problem is usually with the transmission temperature switch. This means that the temperature of the Jeep’s transmission is over the limit. After an hour, it usually drops and allows the car to start. When this happens, you can start by confirming if the transmission fluid is full before checking the temperature sensors.
If it still doesn’t start, you can try starting it at a neutral position. Turn and hold the key until you’re able to switch from park to neutral, but make sure your foot is on the brake pads while turning the key.
There is nothing more disturbing than your Jeep not starting when you need it the most. The fact that it is not starting despite having power means that the problem is not with the battery or the fuel, so you don’t need to jump-start it.
Other than the battery, there are lots of things to look out for that can prevent your Jeep from starting. The issue may be loose wires or corroded battery terminals, which you can deal with on your own. Try identifying and troubleshooting the problem first before you call an expert; that way, you can save yourself some cash intended for repairs.
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