1. Battery:
* Check the battery terminals: Corrosion on the terminals is a frequent cause of electrical problems. Clean them thoroughly with a wire brush and baking soda and water solution. Reconnect the terminals securely.
* Check the battery voltage: Use a multimeter to measure the battery voltage. It should be around 12.6 volts when fully charged. A low voltage reading indicates a weak or dead battery. Jump start the vehicle to see if that resolves the issue. If it does, you need a new battery.
2. Ignition Switch:
* This is the most likely culprit given your symptoms. The ignition switch itself may be faulty, preventing power from flowing to the rest of the system even if the key turns. The stuck key is often a symptom of a failing ignition switch.
* Try jiggling the key: Sometimes, a slightly loose connection in the ignition switch can cause intermittent issues. Gently try wiggling the key while turning the ignition.
3. Neutral Safety Switch:
* Automatic transmission only: This switch prevents the car from starting unless it's in Park or Neutral. A faulty neutral safety switch can prevent the ignition from working correctly. Check that the transmission is definitely in Park or Neutral.
4. Wiring:
* Check for blown fuses: Inspect the fuse box (usually under the hood and/or inside the vehicle) for any blown fuses. Pay close attention to fuses related to the ignition system. Replace any blown fuses with fuses of the same amperage. Important: Don't just replace a blown fuse without identifying and fixing the underlying cause, as the fuse could blow again.
* Look for damaged wiring: Examine the wiring harness leading to the ignition switch for any signs of damage, such as fraying, cuts, or corrosion. This is a more advanced step and requires some electrical knowledge.
5. Steering Column Lock:
* Key might be stuck because of the steering wheel lock. Try gently jiggling the steering wheel while turning the key. If the steering wheel is slightly out of alignment, this can prevent the key from being removed.
6. Ignition Cylinder:
* The ignition cylinder itself could be faulty. This is more involved to fix, often requiring replacement of the entire cylinder.
What to do if you're not comfortable working on this yourself:
If you're not experienced with auto repair, it's best to take your Blazer to a qualified mechanic. Attempting some of these repairs without proper knowledge could cause further damage or injury. The ignition switch is a crucial component, and a misdiagnosis could lead to costly repairs. A mechanic can properly diagnose the problem and perform the necessary repairs safely and effectively.
Remember safety first! Always disconnect the negative battery terminal before working on any electrical components.
