I can't start my 2003 cadillac escalade. Antitheft is eng...

Hello and welcome! My name is [and I can assist you with your question. I am a former master tech and I have worked in this field for 20 years. I specialize this type of problem you are experiencing so I am confident I can assist with this issue. I am sorry you are having this issue and I understand this can be frustrating so I will try my best to help.](//www.justanswer.com/car/expert-amedee/) [While we are working on this issue together, please allow up to 30 minutes (or more) between replies as I might be online helping other customers or offline spending time with family. Please understand I can only see what is on this page and what you have already shared with me. Please keep in mind, I don’t know the history of the vehicle and I don’t know your mechanical ability, however, I will try my best to help.](//www.justanswer.com/car/expert-amedee/) [The phone call prompts are automatic and are coming from the web site, not from me. If you would like to speak on the phone, please request a phone call on your end and I will call you right away.](//www.justanswer.com/car/expert-amedee/) [I am going to start by asking some basic questions to get caught up to where you are at with this situation so I can assist you in a timely manner and provide you with the most accurate and relevant information. I appreciate your time and patience while we are working together on this matter.](//www.justanswer.com/car/expert-amedee/) [My goal is to provide you with a pleasant experience and ensure all of your questions are answered. Please reply back at any time so I can fully answer or address any questions or concerns you may have.](//www.justanswer.com/car/expert-amedee/) [_Please download or save any documents or images I may send you as they will automatically expire after 7 days._](//www.justanswer.com/car/expert-amedee/) [Can I start by getting your first name? Thank you](//www.justanswer.com/car/expert-amedee/)

Brendan

Thank you Brendan. Have you checked the fuses? Is the anti theft light on solid or flashing with the key on?

No to fuses. With the key on there's no anti theft light on at all

Ok so does the [engine](/topics-engine-cadillac/) start and run? Or is the only issue the key fobs are not working?

Drove it last night. Locked the car with the key now it wo t startI turn the key and nothing happens. All the electronics are working but truck no startingIs my time up or something?

Ok you are going to want to start by checking the fuses first. Sounds to me like the computer system may not be powered up or working for some reason. PCM or BCM issue. The first thing we need to do is check all fuses and check the battery with a voltmeter. A fully charged battery must have enough cranking capacity to provide the starter motor and ignition system with enough power to start the engine over a broad range of ambient temperatures. It could be bad or just low on a charge. If it is low on a charge, you need to start by charging it first and then re-testing it. If it is bad, it can still cause a no crank condition even if it’s fully charged. This is due to a bad cell inside the battery. I would recommend to get it load tested at a battery store (maybe even a parts store) or at an automotive repair shop that has a load tester. A battery load test will verify the actual cold cranking amps and the capability of the battery when put under stress (just like if you were to start the engine). This is the best test. Or you can use a voltmeter and measure the voltage while trying to crank the engine over. (Be sure it has a full charge on it which is 12.6 volts.) If the volts drop below 10.0 volts, the battery is bad and needs to be replaced. Just be sure all cables and connections are clean and tight. Not only at the battery, but on the starter, engine and frame! Positive side as well as the negative side. Set your voltmeter to the 20 volt DC scale when checking the battery. **Battery Voltage and State of Charge:** **12.68v . . . . . . . . . . 100%** **12.45v . . . . . . . . . . 75%** **12.24v . . . . . . . . . . 50%** **12.06v . . . . . . . . . . 25%** **11.89v . . . . . . . . . . 0%** If all checks out, make sure that you have full battery voltage on both terminals of the starter when cranking. If full battery voltage (12.6 volts) is present and the starter is not working, then the starter is bad and will need to be replaced! Just be sure all fuses small regular and large size fuses are good under the hood, as well as inside the vehicle Some other possible causes would be a faulty starter, engine or frame ground, faulty fuse block or power distribution center, neutral position switch/PNP, range switch or clutch switch (depending on the transmission), bad ignition switch or a wiring or a connection issue at or after the battery. Most newer cars today use the engine and/or the body module/computer to start and run the engine. The starting circuit is wired through the computer system and if the computer system is not powered up and working correctly this can and will prevent the engine from cranking (depending on your set up). If this is the case, you can check for communication with your computers using a scan tool or code reader and check for codes in the main engine and possibly the body computer of the vehicle. You can also check the starter relay operation and power/ground in and out of the relay to determine what/if any input is missing (if equipped). This will help determine if the issue with a power supply or a ground supply issue (which could indicate a computer issue). Here are some links to help you test/check the battery. (may have to copy the links into your address bar.) [https://www.youtube.com/watch?v=o\_HzL6eKeHk](https://www.youtube.com/watch?v=o_HzL6eKeHk) [https://www.youtube.com/watch?v=COJr7OB23Hw](https://www.youtube.com/watch?v=COJr7OB23Hw) Here is a good battery comparison test. This will help you determine which battery to purchase if you need a new one. [https://www.youtube.com/watch?v=h7rTcBanpMk](https://www.youtube.com/watch?v=h7rTcBanpMk) In some cases the modules lock up preventing the engine from cranking over. This does happen from time to time and can easily be remedied by doing a quick battery disconnect procedure. You're gonna have to be sure to disconnect both cables from the battery and rub the cables together for about 5 minutes. Then reconnect them back up to the battery and then try to start the vehicle. You may get lucky as this might just do the trick. This will discharge all the capacitors inside all of the modules on board the vehicle including both engine control module in the body control module and may allow it to start and run. This is also known as or referred to logic lock. However, this will ONLY work if the issue is a locked up module. If the module is bad or if the problem is not a locked up module it will not work. However, it would be worth a try. Glad I can help. Please let me know if you have any further questions. Thanks and have a great day!

Just bought a brand new batteryIt ran fine all day yesterday and last night it had a hiccup and didn't start but once again I had manually locked my carWere just guessing it seems

You need to pull codes from the computer system next after checking for codes.

Ok well I don't have Anyway to do that thank you for your time

You're welcome!