* Blown Fuse(s): This is the most likely culprit. Check the fuse box(es) (there's usually one under the hood and one inside the car, often under the dash). Look for fuses labeled "lights," "accessories," "radio," or anything that seems relevant. A blown fuse will be visually apparent (broken filament). Replace any blown fuses with the correct amperage. Don't just put in a higher amperage fuse; that can cause further damage.
* Faulty Fuse Box: The fuse box itself could be faulty. A corroded connection or internal short could prevent power from reaching the circuits even if the fuses look good.
* Bad Ground: A poor ground connection somewhere in the electrical system can cause erratic behavior. Corrosion on ground straps or connections can significantly disrupt power flow. Check the ground points for the dash, taillights, and stereo.
* Wiring Problem: A damaged or broken wire in the main power feed to the dashboard or a short circuit somewhere in the system can interrupt power to multiple circuits. This is less likely if it's all going out at once, but possible. Tracing the wiring would be more complex.
* Alternator/Battery Issues (Less Likely): While unlikely to cause only these lights to go out, a failing alternator or a very weak battery could lead to insufficient voltage to power the accessories. Check the battery voltage with a multimeter. The alternator's output should also be tested.
* Body Control Module (BCM) Problem (Less Likely but Possible): In some vehicles, a BCM controls various electrical functions. A malfunctioning BCM could be responsible, but this is less likely as the issue affects seemingly unrelated circuits.
Troubleshooting Steps:
1. Check the Fuses: This is your first step. It's the easiest and cheapest fix.
2. Check the Battery Voltage: Make sure the battery is adequately charged.
3. Inspect Wiring: Look for any obvious damage to the wiring harnesses going to the dash, taillights, and stereo.
4. Check Ground Connections: Clean any corrosion you find on ground connections.
5. Consult a Wiring Diagram: If the above steps don't work, a wiring diagram for your specific 1994 Chrysler New Yorker is essential to help pinpoint the problem. These can be found online or in repair manuals.
If you're not comfortable working with car electrics, it's best to take your car to a qualified mechanic. Working with car electricity can be dangerous if you're not familiar with the procedures.
