* Loose Ground Connection: The most likely culprit. While installing the stereo, you might have accidentally bumped or tightened a loose ground wire somewhere in the dash area. Many dash lights share a common ground, and a poor ground can cause them to malfunction or not illuminate. Fixing the loose ground connection would then restore their function.
* Accidental Wire Connection: It's possible you inadvertently connected a wire during the stereo installation that completed a circuit needed for the dash lights. This is less likely, but possible if you were working near the dash wiring harness.
* Faulty Dash Light Switch or Wiring: The issue might have been a failing dash light switch or a loose connection in the dash light circuit *before* the stereo installation. The vibrations or movements during the install might have momentarily resolved the problem, making it seem like the stereo was the cause.
* Fuse or Circuit Breaker: A blown fuse or tripped circuit breaker related to the dash lights could have been inadvertently reset during the stereo installation. Check your fuse box for any blown fuses associated with instrument panel lighting.
* Coincidence: It's possible the dash light problem was unrelated to the stereo install and just happened to be resolved around the same time.
Troubleshooting Steps:
1. Check the Fuses: Inspect the fuse box for any blown fuses related to instrument panel lighting or accessories.
2. Inspect Ground Connections: Look for any loose or corroded ground connections in the dash area. Pay close attention to the ground wires for the stereo and the main ground points for the dash itself. A loose ground wire can often cause intermittent electrical problems.
3. Examine Wiring: Carefully examine all the wiring near the stereo and dash area for any accidental connections or shorts.
4. Check the Dash Light Switch: If the other steps don't reveal the problem, consider testing the dash light switch itself. This might require more advanced electrical testing knowledge.
If you're not comfortable working with car electrical systems, it's best to take your Blazer to a qualified mechanic or auto electrician for diagnosis and repair. Improper wiring can cause damage to your vehicle's electrical system.
