car suddenly won’t start but radio and lights work, repair shop can’t find problem

All of a sudden my car won't start. It had been running fine before that. It is so strange. The radio and lights work, but it won't start. Sometimes you have to shake the battery cables and other times you need to put it in neutral and it will start. I have taken my car into the shop many times, but they can't find out what is wrong. Do you have any ideas?
Experienced mechanics share their insights in answering this question :
For the vehicle to start, many different systems must work. The most common causes of no-start conditions are the battery, starter, battery cable, ignition switch, or the fuel pump. Any of these can be intermittent issues, which will not always act up. Given that you have had success with shaking the battery cables, this may indicate that one of the cables is failing. A qualified technician, such as one from YourMechanic, will be able to diagnose your starting issue and perform any repairs required.

How to Identify and Fix Common car Problems ?

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The most common causes of no-start conditions are the battery, starter, battery cable, ignition switch, or the fuel pump. Any of these can be intermittent issues, which will not always act up. Given that you have had success with shaking the battery cables, this may indicate that one of the cables is failing.
If your car won`t start, the likely culprit is your electrical system—namely, the battery, alternator or starter. Your car battery provides your vehicle with the power it needs to start.
The most common causes for a Jeep failing to start despite its radio and lights working are issues relating to its battery or other cranking/start-up components, such as the ignition switch, starter, or spark plug. These pieces might be damaged, dirty, or corroded.
Bad Spark Plug Or Broken Distributor Cap/Rotor

If you have a good battery and enough fuel in the gas tank and your car still won`t start, chances are you have a bad spark plug. Why? A bad spark plug will prevent fuel ignition, and the vehicle won`t move.

This same battery is used to power absolutely everything in your car. In fact, it`s even crucial in starting the engine and getting the car going at all. As the radio plays, it draws power from the battery, meaning that it`s possible for your car battery to die while listening to the radio.
The most common car electrical system problems are problems with your car battery, an alternator that isn`t working properly, loose or failed spark plugs, a fatigued solenoid or starter, bad battery cables, electrical fuses that are blown, loose wires, or problems with your ignition switch.
Why won`t my car start but the battery is good? If your car won`t start but the battery is good, the most common cause is a faulty starter – though it could also be to do with your fuel. You may have insufficient fuel to get the car going.
The most common reasons a Jeep had no power relate to the fuel system or the Jeep battery. Other common reasons include wiring issues, a bad alternator, or exhaust issues. Start with checking the battery and that the engine is getting fuel.
If your vehicle won`t start, it`s usually caused by a dying or dead battery, loose or corroded connection cables, a bad alternator or an issue with the starter.
Excessive charges coming from alternator and car battery can entirely damage the starter systems of the car.
One of the best ways to determine if a car fuse has blown is by using a test light. It should illuminate both ends of the fuse, and, if it doesn`t, it needs to be replaced. Sometimes, a blown fuse is caused by a damaged wire, motor, or other part.
Slow or Malfunctioning Accessories

That way, if you`re driving with a failing alternator, you`ll lose power to your radio (or other nonessential accessories) before losing power to your headlights.

If the car won`t start at all and the dashboard lights are flickering, it`s likely that the battery does not have enough charge to crank over the vehicle. In this scenario, you`ll likely need to replace the failed battery.
There are a total of four possible failures that can take place in an electrical circuit: an open circuit, high resistance, short-to-ground and short-to-power.
There are mainly three types namely line to ground (L-G), line to line (L-L) and double line to ground (LL-G) faults.
It can be occurred due to poor wiring in the house or lightning strikes or faulty appliances or damaged power lines. Surges are common and last for a microsecond but if you experience frequent surges lead to equipment damage that degrade life expectancy particularly.
The most common symptom is dimming or flickering lights. This can happen because the electrical current is being interrupted, which causes the lights to dim or flicker. Another common symptom is a blown fuse. If a fuse blows, it`s an indication that too much current is flowing through it.
Examine the circuit board and search for signs such as crushed components, bulges, damaged wires, cracks, misplaced or extra solder, burn marks and scratches that indicate that the board is either bad or requires replacement and professional assistance.
If there is no sound when you turn the key, but the lights and accessories work, it could be the stater relay or starter solenoid. However if there is no sound at all, not even a click, it`s probably your battery.
When you attempt to start the vehicle, is there a clicking sound, but it won`t turn over? That may be a good sign. If a jump gets the car running, but won`t turn over again once it`s shut off, a dead battery is likely the cause.
The most common reasons a Jeep Cherokee won`t start are a dead battery, an alternator problem, or failed starter. Search our network of RepairPal Certified shops near you to speak with a technician about your issue.
Loose wiring, corroded connections, damaged starter components, oil leaks, and a bad relay or fuse are some of the reasons why a starter can fail. As the driver turns on the ignition switch, a current for the starter should flow and get the engine running. If not, the starter might be faulty and require replacement.
Fortunately (spoiler alert) the root cause of a no-crank is almost always simple. Most of the time it`s simply due to a low or dead battery, or voltage drop through a corroded connection. Rule those out before you suspect the starter itself.
A TIPM is an acronym for Totally Integrated Power Module which controls the electrical system in your car. It is a black box made of hard plastic that has power board and fuses inside.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

car suddenly won’t start but radio and lights work, repair shop can’t find problem
ANSWER : For the vehicle to start, many different systems must work. The most common causes of no-start conditions are the battery, starter, battery cable, ignition switch, or the fuel pump. Any of these can be intermittent issues, which will not always act up. Given that you have had success with shaking the battery cables, this may indicate that one of the cables is failing. A qualified technician, such as one from YourMechanic, will be able to diagnose your starting issue and perform any repairs required.

Car won’t start. The check engine light, battery light, and oil change light are coming on. I tried jumping the car and nothing happened. Why won’t my car start?
ANSWER : Hi and thanks for contacting Your Mechanic. If sometimes your vehicle will start with the new alternator and sometimes it won’t, then there is a loose connection in your charging system. Check all of the wires to the alternator and to the battery. Make sure that the battery cables are clean and tight. Make sure that the wires to the starter are clean and tight. A loose ground to the ignition system will cause the vehicle to not crank over. Check all of the ground wires from the battery to the starter. Make sure that they are clean and tight. If you need further assistance troubleshooting your no start situation, then seek out a technician, such as one from Your Mechanic, that can assist you.

Battery and oil light come on when trying to start car, take keys out try again car starts no problem and lights go away
ANSWER : Of course, don’t switch gears without being fully stopped, unless your Owner’s Manual or the manufacturer has alternative advice. However, the gear shift issue has no relation to the no-start problem you are describing. Inasmuch as you only have 6,000 miles on the car, the "constant on and off" that you believe has occurred is meaningless in comparison to the expected total vehicle service life. That is, assume what you perceive as "constant on and off", during merely 6,000 miles, might be equivalent to using the car "normally" for three years. A new car should be trouble free for at least 5 years, unless there is a defect, so your "constant on and off" is not a causal factor for any fault on the vehicle. What you might have is a defect in the ignition switch, or perhaps the immobilizer system, but if the problem is not in the switch itself, clearly there is an electrical problem.

If your vehicle is under warranty, by law the dealer MUST repair the issue you are describing within a prescribed time frame and number of "attempts", otherwise the dealer will run afoul of Federal and state Lemon Laws that give you very specific rights, and recourse (contact an Attorney; we are Mechanics, NOT attorneys). Consequently, if the vehicle is still under warranty, to save yourself money do be sure to seek a resolution from the dealer. If the vehicle is not under warranty, obviously a certified Mechanic from YourMechanic could identify the electrical fault and resolve this for you. If you want to go that route, please simply request a no start diagnostic -electrical system and the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

My dash board don’t work my front light work when I change my light into high beam and my back window won’t go down
ANSWER : As unfortunate as it is, your vehicle would be considered flood damaged. Diagnosing electrical problems in a flood damaged vehicle is nearly impossible. This would take many hours or even days to determine which wiring harnesses and circuits have been affected. Then nearly all of the wiring under the dash would likely require replacement as well as many sensors and switches. On a BMW vehicle, the amount of wires and switches are likely more than that of a lower end vehicle. Due to the inefficiency in cost, you would likely be able to purchase another BMW like yours for less than what it would cost to fix your car. Many insurance companies would consider this type of damage to total out the vehicle unfortuantely.

The car crank but won’t start
ANSWER : Hi there. This does sound like an issue with the wiring. If the check engine light is coming on every now and then this means that when it does not come on there is no power to the computer. This can be the wiring harness issue or an ignition switch problem. I would have to test for voltage to the computer when the problem is occurring to be able to find where the issue lies. If you need assistance, a certified YourMechanic technician can be dispatched to your location to inspect your vehicle’s non-start issue and suggest any necessary repairs.

Car won’t start and no light on the dashboar. Lights, radio, wiper, a/c working. 1994 Honda Civic
ANSWER : Hi there, I would first check for blown fuse(s) and any relays for the ignition and coils. The "smoke came out of the steering wheel" is alarming! You may have a burned out ignition switch, or damaged wiring in the steering column. The "cranks, but doesn’t start" sounds like there is no power to the coil and plugs. I recommend a engine not starting inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

Change interior lights and now it won’t start.
ANSWER : Hi there. There is a short in the switch to the interior lights causing the fuse box to burn fuses and make the car not start up. If you need further assistance with your electrical system, then seek out a professional, such as one from Your Mechanic, to help you.

Whenever I drive 1.5 miles, the s3 light starts blinking and then when I stop my car and come back to it, the car won’t start.
ANSWER : Hello, thank you for writing in. It is difficult to determine the issue without some more information. To start, when the check engine light illuminates, you want to scan the vehicle for diagnostic codes. These are what set the check engine light off, and are meant to tell the driver what the computer has detected is wrong. Codes can be pulled at most automotive parts stores, and by most technicians. Once you have that information you can focus in on one component or system. If the engine is truly overheating, then you want to start by checking your coolant and fluid levels. For more help with diagnosing and resolving the issue, contact our service department to schedule an appointment.