Antitheft key light on jeep wont start

My jeep was running fine. Then last week I went to leave and it would crank but would not start. None of the guages on my dash work, and the key light shows. I have checked the battery and all fuses. O have not done anything new to the vehicle prior.

My car has 215000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hi there, thanks for writing in. You may be having an issue with the anti-theft module on the vehicle. I recommend first try a different key to see if it is the key having an issue. Make sure to not have anything metal on the key ring. If the problem still occurs, then try disconnecting the battery and waiting 10 minutes and then reconnect it. If it then starts okay then it may have just got a voltage spike and problem is gone. If problem persists then the anti-theft module will need to be tested and reprogrammed or replaced by a dealer since they have the special dealer code to activate the module.

If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make any repairs as needed. Hope this helps and best of luck!

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

The most common reasons a Jeep Cherokee won`t start are a dead battery, an alternator problem, or failed starter.
The most common reasons a Jeep Wrangler key won`t turn are a binding steering column/lock, an ignition switch issue, or a problem with the ignition key. Search our network of RepairPal Certified shops near you to speak with a technician about your issue. Oops!
Insert Key and Press Unlock: Put the key to the “RUN” position on the ignition while you press down on the “UNLOCK” button on the driver`s side door. Unlock/Panic: On your key fob hold down the “UNLOCK” and “PANIC” buttons at the same time. Unlock/Lock: Do the same thing, now with the “UNLOCK” and “LOCK” buttons.
If your car has a keyless entry system or remote starter, and is not starting (anti-theft light flashing), the battery inside your keyless entry fob may be dead (try changing the battery), there may be a fault in the fob itself (try a second fob for your car if you have one), or the receiver may not be picking up the …
The most common reasons a Jeep Grand 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.
The most common reasons a Jeep Cherokee won`t start is because of a bad battery, corroded battery terminals, or a bad starter. Other common reasons a Jeep Cherokee won`t start are a bad alternator and a broken or failing fuel pump.
Put the key in the ignition and rotate forward two clicks to the “On” position that makes the dashboard light up, but don`t try starting the car. Leave the key there for 15 minutes; it doesn`t always take that long, but it can. After that time, check to see if the anti-theft light has gone out, if one was lit up.
Check the door lock

In some cases, the car`s anti-theft system is linked to a door lock mechanism. To disable it, you need to locate a small switch or release lever on the door panel and engage it. This will cause the car`s security system to be disabled.

However, there are a few things you may do if you`re wondering how to stop the anti-theft mechanism without a key. One common method is to press and hold the “unlock” button on the car door for around 10 seconds; this should turn off the security system.
However, there are a few things you may do if you`re wondering how to stop the anti-theft mechanism without a key. One common method is to press and hold the “unlock” button on the car door for around 10 seconds; this should turn off the security system.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Fuel pump engages. Batery good, alternator good volts, jump start helps when wont start. Temp does not matter. Intermittent?
ANSWER : Hello. Thank you for writing in. There are several reasons your vehicle may only start when jump starting. The first and most common is a build up of resistance that is causing you to need a boost of voltage to get the engine started. This may be due to poor battery cables, a bad ground connection, a poor starter solenoid, and a couple of other issues. The first thing you want to do is perform a visual inspection of the starting system. Make sure there is no corrosion build up in the battery cables. You can also check the resistance across these wires and make sure you have a solid connection between components. You then want to make sure the starter solenoid is doing its job. It is responsible for taking the small amount of electricity sent by the ignition and turning it into a huge electrical charge that is strong enough to push over the engine with the help of some gear ratios in its favor. Do some more testing, and stick to the basics before assuming its something seriously complicated.

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.

My Jeep started fine. I adjusted the tilt steering. The airbag light came on but it continued to run fine. Shut Jeep off and would not start again
ANSWER : The air bag light comes on when the computer detects an issue with the vehicle’s air bag safety system. This can have many potential causes, including a faulty sensor, wiring, air bag unit, computer, among other things. If you were having issues with the steering column, it may be possible that one of the airbag system components located in the steering column, such as an airbag module or sensor, has had an issue. If these components are linked to the starting system then this may be part of the reason why the vehicle is not starting. If the engine is cranking when you turn the key, then that is a good sign that the starter is getting power, so that rules out most of the no start issues related to the starting and electrical systems.

It may also be possible that the no start condition is a completely separate issue from the airbag light, as there are many things, not related to the airbag system, that can cause a no start condition. A few common non air bag related causes are issues with the fuel, ignition, or engine management systems. If any of the components to these systems, such as the fuel pump, ignition coils, or an engine management sensor, fail or have an issue, they may cause the vehicle to Retrieving the trouble codes using a scan tool capable of reading airbag system codes as they will likely shed some light on what the cause of the issue may be, or if the two are related. If you are unsure, I would recommend having a professional technician, such as one from YourMechanic, come to your location to diagnose and repair the cause of the no start condition.

Car won’t start and shakes while turning the key – 2003 Saturn L300
ANSWER : Hello. These lights can mean that there is a serious issue going on or that there may be an electrical malfunction. I usually check and see if there is oil pressure and check to make sure that the charging system is working.

If they both are, then the circuits needs to be tested as it is common to have a battery cable issue, an ignition switch, or a body control module fail and cause these symptoms. If you need to have these warning lights checked, consider a certified mechanic, such as one from YourMechanic, who can come to your home or office to determine why the car is not starting.

Put key in ignition. Lights and everything come on for a second, then went off as I turned the key. Now no power, key stuck
ANSWER : Hi, thanks for writing in. This sounds like your battery cable connections are corroded or loose at the battery. Try to see if the battery connections are loose by wiggling them and see if power returns. If power returns, then have the cables removed, cleaned, and reconnected to test the battery. Hope this helps and best of luck!

Vehicle won’t start, once it’s jump started it only stays running until you turn it off, then it work start again without jumping.
ANSWER : Hi there. There could be two problems here. It is possible that your battery is bad and will not take a charge from your alternator while driving. In that case every time you shut your car off you will not have enough juice to start it again. Inspect your battery – it should have at least 12.5 to 13 volts to start your car, if it doesn’t you will need to replace the battery. The second problem could be that your alternator is bad and not charging your battery, in this case you will need to replace your alternator. Both the battery and the alternator can be tested in your car. If you would like to have the car checked for you, a certified professional from YourMechanic can come to your car’s location to diagnose the starting problem and proceed with repairs.

Car was sometimes not starting, not even cranking when i turned the key then after a few times itd start. Now it ont start at all
ANSWER : Hi there:

Without being there to inspect your vehicle, or having information about what type of car, truck or SUV you own, it’s very hard for us to give you some advice. You might want to have a professional mobile mechanic complete a car is hard to start inspection; so they can come to your location and determine why your vehicle is having these issues.

Car wont start–check engine, oil pressure, and battery light all on
ANSWER : Hi There,
If your oil pressure falls below a specific level, the ECM (car’s computer) will automatically shut the engine down to avoid further damage to the engine. This is done as a safety precaution. Typically, the oil pressure light will come on when you are in fact low on oil, the oil pump is not pumping oil properly or in some cases when the oil pressure sensor is faulty providing a false reading. In any case, this should be looked at as soon as possible by a qualified mechanic. I would suggest having one of our experts here at YourMechanic come to your location to take a look at your vehicle.