We know you must be thinking that there is something severely wrong with your vehicle if your car won’t turn on, but lights come on. Just because the electrical components seem to be working in your car doesn’t mean that everything runs smoothly and properly in the other internal systems.
Since there are various systems within the car, the transmission, engine, and other issues, like the fuel system and the liquid delivery system, could have completely separate damage from any lighting components.
If your car won’t start, but lights come on, and the radio is turning on, it could be a few different problems. The most likely culprit for this issue usually deals with the battery. The reason why the radio, the dashboard warning lights, the headlights, and other electrical components can get power while the engine cannot has to do with an interrupted path of flow of power directed towards the engine.
If this happens, you will notice your car won’t start, but lights come on, which can indicate a serious and dangerous issue in your car that might only get worse over time.
Reasons Why Car Won’t Start But Lights Come On
Let’s check out the main reasons why your car won’t start but lights come on. Since it can be due to various issues, you must diagnose and troubleshoot the root cause of the problem so that you can prevent it from getting any worse or fixing the wrong part in your vehicle.
Fuses and Fusible Link Damage
First, check your car’s manual to find the fuse box’s location to see if the fuse or wire is damaged. Suppose the metal wire in the plastic is damaged or disconnected. In that case, a damaged fuse might prevent power from getting to the starter relay, which is necessary to provide the ignition, the spark, and the power to run your vehicle. Any visible damage to a fuse or fusible links can cause the “car won’t start, but lights come on ” issue in your vehicle.
Faulty Ignition Switch
If you determine if the fuse is in good shape, then the real problem is the car’s ignition switch. The ignition switch is the electrical switch inside that your key touches when the mechanical part is inserted into the ignition. In some situations, the ignition switch can only give the electrical components power and avoid the engine starter. If this is the case with your ignition switch, you can experience the “car won’t start but lights come on” situation.
Signs of Failing Ignition Switch
There are noticeable signs of a failing ignition switch. One sign is that the car can stall while driving. If this happens, it is a very hazardous driving situation, as the ignition will cut off power to the fuel systems. The second sign of a failing ignition switch is that the ignition switch might constantly be in the “on” position, always giving power to the fuel pump and overloading the sensor.
In addition, another sign of a failed ignition switch is when you have trouble turning on the electrical accessories in your vehicle. When you insert the key and turn it, the accessories might not power on. If this is the case, then you will have ignition problems, fuse issues, and wiring issues that can cause the “car won’t start, but lights come on” issue.
Analyzing a faulty ignition switch’s symptoms can help you prevent the “car won’t start but lights come on” issue. Diagnosing and remedying a broken ignition switch is a bit more complicated than checking for a broken fuse. However, the good way to check is that if the instrument panel and dashboard lights do not turn on when the key ignition is moved, the problem is most likely with the ignition switch.
One of the main reasons why the engine might not be starting is a dead or dying battery. Just because some of the electrical parts are working, they can sometimes run on a deficient charge – a charge that is so low your car won’t start, but lights come on.
Like the headlights, radios, and other electronics, some parts might only require a minimal amount of power. This means that these components can function normally on a very low or almost dead battery. Since these parts need no more than usually 20-30 amps, they can run on a nearly dead battery and prevent any voltage drainage or waste.
However, engine starters, which can make your car turn over, require nearly 300 amps at once. This is usually too much for a battery with just a low charge. This high power demand can cause the “car won’t start, but lights come on” issue.
Test the Battery
To see if your battery has a low charge or is completely dead, use a voltmeter to analyze the power level. If the battery does not pass a load test, then this means the battery needs to be charged. If it can gain a charge from another battery and the vehicle can start after getting a jump, you have fixed it. However, if it doesn’t start, a damaged fuse might be the problem, a broken ignition switch, or a bad starter.
Blown Fuse Signs
Luckily for all drivers, you can tell when your car has blown a fuse. Detecting a damaged fuse is one of the first steps in figuring out what prevents the engine from starting. Analyzing and diagnosing the broken fuse’s location can help you prevent the “car won’t start but lights on” scenario in your vehicle.
The signs of a faulty fuse are that your accessories will lose power, the damaged fuse will appear broken or disconnected, or circuits start to overload. This can cause your engine not to turn over but your lights to come on.
If the battery is dead and not working correctly, you will need to get a replacement or repair the battery. Sometimes, you need to decide if it is better to repair or replace the battery depending on your car’s value, and the cause of the “car won’t start, but lights come on” situation.
Another reason for the “car won’t turn over, but lights come on” situation is that the starter is not working correctly. The starter in your car is the electric motor cranking your engine to turn on your vehicle. The entire system consists of the motor, the solenoid, which transports the battery power to the motor, and the flywheel.
Whenever your car will not start, and the battery is charged, the starter motor is usually the culprit of the issues.
First, the starter can crank, but the car will not start. This is usually due to battery failure, poor connections, damaged battery terminals, or a dead battery. Another sign of your “car won’t start, but lights come on” issue is that you have to jiggle the key to start the car. This shows you have a bad ignition switch, and the solenoid is not being activated. In addition, the car might start when it is in neutral, but not when it is in the park position. If this occurs, you have a damaged neutral safety switch that prevents your car from shifting correctly.
If you find that your car starter is the issue of why you have the “car won’t start, but lights come on” situation, you need to replace the starter in your vehicle. A mechanic can do this, but you can save some money by doing this replacement yourself if you have the tools and knowledge.
Ground Cable Wiring Problem
Another cause of the car not starting can be a ground cable problem. If the ground cable between the body and the engine is bad, the power flow will be cut off and restricted. This means that the engine power will not be able to crank the engine.
Ground Cable Symptoms
Signs of a ground cable problem in your include dim lights, flickering lights, electrical devices turning on and off, a faulty fuel pump, clutch slipping in the AC compressor, intermittent sensor failure, damaged throttle or damaged cables, and hard starting. Along with all of these issues, you may also find that you experience the loss of ability to start and a dead battery, all of which can cause the “car won’t start, but lights come on” situation.
Causes of bad engine grounds and the starter clicking can be caused by damaged ground terminals or wires, a loose ground battery terminal, or a faulty component installation.
As you can see, there are many causes of the “car won’t start but lights come on” scenario in your vehicle. By diagnosing if the problem stems from the battery, the ground cable, the fuses and fusible links, the starter, or the ignition switch, you can determine the best way to fix your car.