A quick guide to problems and solutions to why the ignition key won’t start the car. Possible reasons and solutions.


Table of Contents

Why my car won’t start?

Ford transponder key coding on site
Ford transponder key coding on site

There may be a few reasons why the ignition won’t start the car. Some of them are mechanical (such as a dead battery) and some of them are transponder key-related issues.

We will go over the signs to help you determine the cause and the solution.

First, let’s figure out if this is a mechanical problem or a key-related problem.

connecting coding machine to car on site locksmith or dealer (2)
connecting coding machine to car on site to code new key

There is an easy way to figure this out.

In case the key turns in the ignition AND the lights, radio, and signals are working it means the battery is good and therefore it is a key related issue.

If the key turns in the ignition but the lights, radio, etc. are not working, this is a mechanical problem and you should get advice from a mechanic.

In case the key won’t turn in the ignition, please visit our blog post.

So, we now know that the battery is good, the key turns fine in the ignition, the lights and radio are on and working fine and there is even a clicking noise. What is the problem?

Step Two: Bad key or uncoded key

Transponder key – inside look and chip

If the situation above sounds familiar, it looks like the problem is a transponder key or chip key-related issue.

Most models made after 2000 are equipped with a transponder security system built in the car’s computer.

This is a method to prevent unauthorized keys from starting the car. In other words, keys must be programmed into the car’s computer to start the car.

If everything works fine, but the car won’t start, it means that either the key isn’t program or you have the wrong chip value for the key.

Step Three – the solution:

First, you must verify that the key you have is a transponder key AND has the right value AND reprogram the key by an automotive locksmith or dealer.


Here is an example: Non chip key VS Chip key

Non chip key - left and chip key - right
Non chip key – left and chip key – right

Above, two keys. Non-transponder key and a transponder key, have the same keyway (meaning both will turn the ignition on but one won’t start the car since it isn’t a transponder key).

You must make sure that if your car is transponder equipped, you have a transponder key. You can’t get this key copied or duplicated at the hardware store as it needs to be programmed.

Second, make sure you have the right value for the transponder key.

Two keys that look the same with different chip inside
Two keys that look the same with different chip inside

Above, two transponder keys look the same, but carry a different chip value, and therefore one will start the car after programming and the other won’t.


When does it happen? When should I pay attention to programming or reprogramming? I just changed my battery and disabled the alarm. Is this in any way related?

Auto locksmith coding a new transponder key with a special coding tool
Auto locksmith coding a new transponder key with a special coding tool

The transponder system is related to the car’s battery, ignition, and alarm system.

Our professional locksmiths have seen many cases where changing the car’s battery results in erased keys, meaning the computer no longer recognizes the older keys that used to work just fine.

Moreover, installing an alarm may result in the same as well as changing the ignition cylinder.

The situations mentioned above are the most common reasons why the key won’t start, loses its value, and therefore require reprogramming.

Moreover, trying to start the car with the non-program key or non-transponder key, or wrong chip value key may result in the same.

What is the bottom line? What should I do now?

A locksmith is cutting a new Kia key
A locksmith is cutting a new Kia key

You should contact the dealer or an automotive locksmith. Explain the situation in detail.

If you made any changes, such as disassembling the car’s battery, attempted to code an additional key yourself, or tried to start the vehicle with a non-coded key, provide this information as well.

Remember, a locksmith or dealer must know what may have caused the problem to solve it fast and efficiently.

Make sure you know the exact year, make, and model, as well as the VIN number of the car. This will help to verify you have the correct chip/value key.