1. Incorrect battery installation: Ensure the battery is installed correctly, with the positive terminal connected to the positive battery post and the negative terminal connected to the negative battery post. Double-check the connections to make sure they are tight and secure.
2. Faulty battery: Even a new battery can be defective. Check the battery terminals for signs of corrosion or damage, and ensure the battery is securely mounted. You can also try jump-starting the vehicle using another battery to see if the battery is the issue.
3. Starter problems: If the battery is properly installed and charged, the problem could lie with the starter. The starter is responsible for cranking the engine, so if it fails, the engine won't start. Common starter problems include worn-out brushes, a faulty solenoid, or a damaged starter motor.
4. Fuel system issues: Check the fuel system to ensure fuel is reaching the engine. Look for leaks, kinks, or blockages in the fuel lines. You can also try starting the vehicle with the fuel cap loose to see if a clogged fuel vent is causing the issue.
5. Ignition system problems: Check the ignition system, including the spark plugs, spark plug wires, distributor (if equipped), and ignition coil. Look for signs of damage, corrosion, or loose connections.
6. Electrical issues: Check the electrical connections and wiring throughout the engine bay. Look for loose, damaged, or corroded wires or connections. You can also try wiggling the wiring harness while trying to start the engine to see if a loose connection is preventing it from starting.
7. Security system: Some Trailblazers have a security system that can prevent the engine from starting if it's not disarmed properly. Make sure the key you're using has the correct chip and is programmed to the vehicle's security system.
