# Why won't my car start? **Verdict:** Drive to a shop this week - **Most common cause:** Weak or dead battery - **Urgency:** This week - **Typical fix:** $5-$1,300 - **Causes to check:** 6 ## Quick answer When a car won't start, the most common reason is a weak or dead battery, followed by corroded battery cables, a failing starter, or a charging system that stopped recharging the battery. What you hear when you turn the key or press start (nothing, clicking, or normal cranking) is the fastest way to narrow it down. ## What is happening? Starting a car is a chain. The battery sends a large burst of current through the cables to the starter motor, which spins the engine. At the same time the car checks the key or fob, the fuel pump builds pressure, and the computer begins firing spark and fuel. Once the engine runs, the alternator takes over and recharges the battery. A no-start means one link failed, and the sound you hear tells you which part of the chain to look at. Silence or clicking points to the electrical side: battery, cables, starter or the key system. Normal cranking without the engine catching points to fuel, spark or a sensor, which has its own page. This matters because guessing is expensive: many good starters and batteries are replaced when the real fault was a loose clamp or a dead alternator, and a battery that is drained repeatedly loses capacity for good. ## What causes it? The 6 most likely reasons 1. **Weak or dead battery** (most common), $150-$350. Batteries lose capacity with age, heat and cold. Lights left on, short trips, or a battery older than about 3 to 5 years can leave too little power to turn the engine. Hot climates shorten battery life, and the failure often shows up on the first cold morning. Slow cranking, dim lights or rapid clicking are the usual signs. How to confirm: Dash lights are dim or flicker, you hear rapid clicking, or the engine turns over slowly. If a jump start gets it running right away, the battery or charging system is the problem. Fix: Recharge or replace the battery. 2. **Loose or corroded battery terminals** (common). White, green or blue crust on the terminals, or a loose clamp, blocks the large current the starter needs even when the battery is fine. The dash may light up and then go dark when you turn the key. Corrosion builds faster on older batteries and in humid climates, and tightening or cleaning the clamps often solves it for free. How to confirm: With the engine off, look at both battery posts for crust and try to twist each cable clamp by hand. Any movement or buildup is a likely culprit. Fix: Clean and tighten terminals, replace cable ends if damaged. 3. **Failing starter motor or solenoid** (common), $350-$900. The starter is the electric motor that spins the engine. When its solenoid contacts or motor brushes wear out, you get a single click, a whirring sound without the engine turning, or nothing at all, even with a good battery and bright lights. Starters often fail gradually, working on some tries and not others, especially when the engine is hot. How to confirm: Dash lights and headlights stay bright when you try to start, but you hear one click or nothing. A jump start does not help. Fix: Replace the starter. 4. **Alternator not recharging the battery** (common), $400-$900. If the alternator stops charging, the car runs on the battery alone until it is drained, then will not restart. The battery light often came on while driving, and lights or gauges may have dimmed or flickered. A jump gets the car going, but it dies or will not restart later. Replacing only the battery will not fix it. How to confirm: The car starts after a jump but dies again within minutes or will not restart later. A shop or parts store can test charging voltage for free; about 13.5 to 14.7 volts with the engine running is normal. Fix: Replace the alternator (and battery if damaged). 5. **Key fob battery or immobilizer problem** (less common), $5-$400. Push-button and chipped-key cars will not crank or start if the car does not recognize the key. A security or key light usually flashes on the dash, or the car shows a key not detected message. A weak fob battery is the simplest cause. A damaged key chip or a fault in the immobilizer system needs a dealer or locksmith. How to confirm: A key or security light flashes, or the dash says key not detected. Try the spare key, or hold the fob against the start button (many cars read a dead fob that way). Fix: Replace the fob battery, or reprogram the key. 6. **No fuel reaching the engine** (less common), $20-$1,300. A failed fuel pump, blown fuel pump fuse or relay, or simply an empty tank lets the engine crank normally but never fire. On many cars you can hear the pump hum for about two seconds when you switch on the ignition; if that hum is missing, fuel delivery is a strong suspect. How to confirm: The engine cranks at normal speed but never catches. Turn the key to on without starting and listen near the rear seat for a 2-second hum; no hum points to the fuel pump circuit. Fix: Replace the fuel pump, fuse or relay. ## How to narrow it down at home 1. Turn the key or press start and listen. Nothing at all, rapid clicking, a single click, or normal cranking each point to different causes. 2. Turn on the headlights and watch them while you try to start. If they dim sharply or go out, the battery or its connections are the problem. 3. Try a jump start or a portable jump pack. If the car starts and keeps running, the battery or alternator is the likely cause; if nothing changes, look at the starter, key or fuel. ## Is it safe to drive? > **Drive to a shop this week.** A car that will not start is not a safety risk by itself, but do not keep cranking for more than 10 seconds at a time. If it only starts with a jump, drive straight to a shop for a battery and charging test, because it may not restart. ## When does it become urgent? - You smell fuel, see smoke, or notice a burning smell when you try to start: stop trying. - The battery is swollen, cracked or leaking, or smells like rotten eggs: do not jump-start it. - Cranking makes a loud grinding or banging noise, which can damage the starter or flywheel. - The car only starts with a jump and the battery light comes on while driving. ## What will the repair cost? | Cause | Fix | Typical cost | | --- | --- | --- | | Weak or dead battery | Recharge or replace the battery | $150-$350 | | Failing starter motor or solenoid | Replace the starter | $350-$900 | | Alternator not recharging the battery | Replace the alternator (and battery if damaged) | $400-$900 | | Key fob battery or immobilizer problem | Replace the fob battery, or reprogram the key | $5-$400 | | No fuel reaching the engine | Replace the fuel pump, fuse or relay | $20-$1,300 | Detailed breakdowns: [car battery replacement cost](/cost/car-battery-replacement), [starter replacement cost](/cost/starter-replacement), [alternator replacement cost](/cost/alternator-replacement). ## What to tell your mechanic Tell the shop exactly what happens when you try to start: no sound, one click, rapid clicking, slow cranking or normal cranking. Mention whether the dash lights dim, whether a jump worked, how old the battery is, and whether a security light was flashing. They will test the battery, check cable voltage drop, test the starter draw and check alternator output. ## How to prevent it - Have the battery load-tested each year once it is three years old, and before winter. - Clean white or green corrosion off the terminals and make sure the clamps are tight. - Drive at least 20 to 30 minutes at a time now and then if most trips are short. - Use a battery maintainer if the car sits for more than two weeks at a time. - Replace the key fob battery when the car starts asking you to hold the fob near the button. ## Which models get the most electrical complaints? | Model | Electrical complaints to NHTSA | All complaints | | --- | --- | --- | | [Subaru Outback](/vehicles/subaru-outback) | 1,882 | 5,788 | | [Honda Pilot](/vehicles/honda-pilot) | 1,692 | 5,776 | | [Jeep Cherokee](/vehicles/jeep-cherokee) | 1,566 | 7,486 | | [Jeep Grand Cherokee](/vehicles/jeep-grand-cherokee) | 1,533 | 5,477 | | [Jeep Wrangler](/vehicles/jeep-wrangler) | 1,470 | 6,195 | | [Honda Accord](/vehicles/honda-accord) | 1,390 | 5,912 | | [Ram 1500](/vehicles/ram-1500) | 1,367 | 7,390 | | [Honda CR-V](/vehicles/honda-cr-v) | 1,288 | 8,952 | | [Chevrolet Silverado](/vehicles/chevrolet-silverado) | 1,254 | 7,658 | | [Chrysler Pacifica](/vehicles/chrysler-pacifica) | 1,254 | 4,083 | Owner complaints filed with NHTSA in the electrical category for 2015-2026 models of 63 popular cars. Counts follow sales as well as reliability, so compare each with the model's total. ## Trouble codes that often go with it - [P0335](/codes/p0335): Crankshaft Position Sensor "A" Circuit - [P0340](/codes/p0340): Camshaft Position Sensor "A" Circuit (Bank 1 or Single Sensor) - [P0230](/codes/p0230): Fuel Pump Primary Circuit - [P0562](/codes/p0562): System Voltage Low ## Frequently asked questions ### How do I know if it's the battery or the starter? If a jump start fixes it, it is almost always the battery or charging system. If the dash lights stay bright but you hear one click or nothing, the starter is more likely. A free battery test at a parts store settles it in minutes, and many will also test the starter and alternator. ### Why won't my car start but the lights work? Because lights need very little power while the starter needs hundreds of amps. A battery can run the dash but still be too weak to crank, and a bad starter or loose cable gives the same result. Watch whether the lights dim sharply when you try to start, which points to the battery. ### Can cold weather stop a car from starting? Yes, cold weather is one of the most common triggers. Cold reduces a battery's available power and thickens engine oil, so an aging battery that worked in fall can fail on the first cold morning. Parking in a garage or using a battery maintainer helps an older battery get through winter. ### Should I keep trying to start a car that won't start? No, try a few times in bursts of no more than 10 seconds, with a pause of about a minute between. Long cranking can overheat the starter and drain the battery further. If it still will not start, move on to a jump start, check the fuel level, or call for help. ### How much does it cost to fix a car that won't start? It can be free if the fix is tightening a battery clamp, or about 150 to 350 dollars for a new battery at an independent shop in 2026. A starter runs about 350 to 900 dollars and an alternator about 400 to 900 dollars. Fuel pump repairs can reach about 1,300 dollars. ### What does it mean when my car makes no sound at all? Complete silence usually means no power is reaching the starter: a fully dead battery, a loose or corroded cable, a bad neutral safety switch, or a key the car does not recognize. Check that the shifter is fully in Park, try Neutral, and look for a flashing security light on the dash. ### Can I jump-start my car myself? Yes, if the battery is not cracked, swollen or leaking. Connect red to the dead battery's positive, red to the good battery's positive, black to the good battery's negative, and the last black clamp to bare metal on the dead car's engine. Follow your owner's manual, since some cars have dedicated jump points. ### Why does my car start after a jump but not on its own? Either the battery can no longer hold a charge or the alternator is not recharging it. A battery and charging test tells you which. If the car dies again soon after a jump or the battery light is on, the alternator is the likely cause. An unseen electrical drain is another possibility. ### How long does a car battery last? Most car batteries last about 3 to 5 years, less in hot climates and with lots of short trips. Heat speeds up the chemical wear inside, even though the failure often appears in cold weather. Have it tested yearly after the third year so you can replace it before it strands you. ### Can a bad key fob stop a car from starting? Yes. If the fob battery is weak, a push-button car may not detect the key and will not start. Most cars have a backup: hold the fob against the start button or place it in a marked slot, as shown in your owner's manual. Replacing the fob battery is usually cheap and easy. ## Sources - [Battery Council International](https://batterycouncil.org/) - [Car Care Council: Car care guide](https://www.carcare.org/car-care-guide/) ## Other car problems - [Why does my car battery keep dying?](https://diagxcar.com/symptoms/car-battery-keeps-dying) - [Why does my car click but not start?](https://diagxcar.com/symptoms/car-clicks-but-wont-start) - [Why are my headlights flickering?](https://diagxcar.com/symptoms/headlights-flickering) - [Why does my car make a clicking noise when I turn?](https://diagxcar.com/symptoms/clicking-noise-when-turning) - [Why won't my car go into gear?](https://diagxcar.com/symptoms/car-wont-go-into-gear) - [Why is my engine knocking?](https://diagxcar.com/symptoms/engine-knocking-noise) - [Why does my car stall while driving?](https://diagxcar.com/symptoms/car-stalls-while-driving) - [Why does my car smell like rotten eggs?](https://diagxcar.com/symptoms/car-smells-like-rotten-eggs) - [Why does my car make a humming noise while driving?](https://diagxcar.com/symptoms/humming-noise-while-driving) - [Why does my car smell like gas?](https://diagxcar.com/symptoms/car-smells-like-gas) ## Repair costs - [Car battery replacement cost](https://diagxcar.com/cost/car-battery-replacement): $150-$450 - [Starter replacement cost](https://diagxcar.com/cost/starter-replacement): $350-$900 - [Alternator replacement cost](https://diagxcar.com/cost/alternator-replacement): $450-$1,100 ## How long parts last - [How long do car batteries last?](https://diagxcar.com/how-long/car-battery): 3-5 years - [How long do alternators last?](https://diagxcar.com/how-long/alternator): 7-10 years - [How long does a car starter last?](https://diagxcar.com/how-long/starter) ## Trouble codes that lead here - [P0230 Fuel Pump Primary Circuit](https://diagxcar.com/codes/p0230) - [P0335 Crankshaft Position Sensor "A" Circuit](https://diagxcar.com/codes/p0335) - [P0339 Crankshaft Position Sensor "A" Circuit Intermittent](https://diagxcar.com/codes/p0339) - [P0562 System Voltage Low](https://diagxcar.com/codes/p0562) - [P0571 Brake Switch "A" Circuit](https://diagxcar.com/codes/p0571) - [P0705 Transmission Range Sensor "A" Circuit (PRNDL Input)](https://diagxcar.com/codes/p0705) ## Warning lights linked to this - [Battery (charging system) warning light](https://diagxcar.com/warning-lights/battery) ## Terms explained - [What is Alternator?](https://diagxcar.com/glossary/alternator) --- Source page: https://diagxcar.com/symptoms/car-wont-start Updated: 2026-11-03 General information, not a substitute for a qualified mechanic.