1. Check the Battery and Connections:
* Battery Voltage: Use a multimeter to check the battery voltage. It should be around 12.6 volts when fully charged. A low voltage could prevent accessories from powering up, even if cranking is still possible (though weak).
* Clean Battery Terminals: Corrosion on the battery terminals can hinder current flow. Clean them with a wire brush and baking soda and water solution. Make sure the connections are tight.
* Battery Cables: Inspect the battery cables for any damage, fraying, or loose connections.
2. Ignition Switch:
* This is the most likely culprit. The ignition switch is a mechanical and electrical component that distributes power based on the key position. If it's faulty, it might not be sending power to the accessories even though the starter circuit still functions. Replacing the ignition switch is a fairly common repair, but can be tricky depending on the year and model of your Firebird. You might need special tools or even removal of the steering column shroud.
3. Ignition Switch Wiring:
* Check for broken or loose wires: Carefully inspect the wiring harness connected to the ignition switch. Look for any broken, frayed, or corroded wires. Pay close attention to the wires leading to the fuse box and the instrument cluster.
* Poor Connections: Even if the wires aren't broken, loose or corroded connections at the terminals can prevent power from flowing. Clean these connections.
4. Fuses and Relays:
* Check the fuses: Look in the fuse box (under the hood or inside the car, depending on your model year) for any blown fuses related to the ignition system, accessories, or gauges. Replace any blown fuses with the correct amperage.
* Relays: Some accessories might be controlled by relays. Check these as well.
5. Instrument Cluster:
* While less likely, a fault within the instrument cluster itself could prevent the gauges from lighting up, even if power is reaching them. This is harder to diagnose without specialized tools.
6. Neutral Safety Switch (Automatic Transmission):
* If your Firebird has an automatic transmission, a faulty neutral safety switch can prevent the car from starting, *even if the engine cranks*. It won't directly affect the accessories powering up, but it's worth checking, especially if you're sure the engine cranks properly and the problem seems to be solely accessory and gauge power.
Next Steps:
* Consult a Repair Manual: A repair manual specific to your year and model of Firebird will be invaluable. It will show you wiring diagrams, fuse box layouts, and step-by-step instructions for replacing parts.
* Seek Professional Help: If you're not comfortable working on your car's electrical system, take it to a qualified mechanic. Improperly working on car electrical can lead to further damage.
Remember safety first! Disconnect the battery's negative terminal before working on any electrical components. Good luck!
