Even a truck as huge and as tough as the Chevrolet Trailblazer is not exempted from having cracked headlights or busted bulbs. While these are common problems that are easy to diagnose, there are other headlight issues that you might encounter. So if lately, you've been noticing that something is wrong with your headlights, here are our insights on how to troubleshoot various headlight problems:
This can simply mean that one of the headlight bulbs has burned out. Headlight bulbs, just like any other lights, have a limited lifespan since they are used frequently. But to be sure, you may also inspect the electrical connector for rust spots or damage. When the thin tungsten filament inside the bulb burns out, then there is no other solution but to replace the bulb itself. If you have an incandescent bulb, you may opt for a xenon replacement bulb that offers a longer lifespan and brighter illumination. Make it a point to replace your headlight bulbs every five or six years or earlier, especially if you notice that they are already dimming or blinking.
This is usually caused by a bad headlight relay, a defective headlight switch, a fuse issue, or a wiring fault. To determine which one is causing the problem, check the main fuse for the headlight circuit. Look for a blown fuse, replace it with a new one, and try to turn the lights on. If the fuse blows, there could be an overloading in the headlight circuit that needs to be repaired. Next, inspect the headlight relay by pulling it out and shaking it. If you notice a rattling inside it, you need to replace the relay. If the lights still won't turn on, then the problem might be the switch. Replacing it is a bit complicated, so we advise you to let an expert mechanic do it for you.
This is usually caused by a problem with the charging system. It could either be due to a bad alternator or slipping alternator drive belt. When this happens, you may check the charging voltage with the engine idling. There's something wrong if it is less than 13 volts. Have it checked by your mechanic; the voltage at the battery should be about 13.5 to 14.5 volts.