We don’t have to tell you how important headlights are, or how dangerous non-functioning headlights can be. There are a number of things that could cause this problem, but one thing remains consistent: it’s an issue that needs to be addressed immediately. Even if you drive exclusively in the daytime, putting off repairing headlights is hazardous–not to mention illegal. Check out four potential causes below, and then schedule your service appointment immediately.
4. Blown Fuse
One of the first things you should do in the event of an electrical problem like nonfunctional headlights is to check the appropriate fuse. Your Toyota owner’s manual will have a list of what each fuse corresponds to; find the fuse for your low beam headlights, remove it, and inspect it. If the fuse is burned out, replace it with a functioning fuse of the same amperage and see if that does the trick. If not, it could be due to one of these other issues.
3. Wiring Problem
The wiring in your car is complex, and faulty wiring could cause the headlights not to work. In fact, wiring trouble could also cause a fuse to blow, since fuses burn out when excess current runs through a system. If it’s a one-time issue, the fuse might just blow once. But if it’s due to an underlying wiring problem, the replacement fuse won’t last, either. Because of the complexity of the wiring in your vehicle, it’s recommended that you leave the diagnosis to the experts.
2. Damaged Relay
When you flip a light switch in your house, the switch completes a circuit and turns on the lights. In your car, things work a bit differently. The switch that you flip doesn’t actually complete the circuit. Rather, it sends a little bit of energy to a relay, and the relay completes the circuit. If the relay has gone bad, it may be receiving the electricity from the switch, but could be unable to complete the circuit. In cases like this, a new relay may be required.
In some cases, the high beams and low beams have separate relays. If one of these relays goes bad, the other one may still work.
1. Burned-Out Bulbs
If the headlights on both sides aren’t working, you might not suspect burned-out bulbs to be the cause. After all, bulbs usually don’t burn out at the same time. However, it’s a more common cause than you might think. This is because headlights today are much brighter. You might not realize that one bulb has burned out, because the other one is providing enough light. It’s only when the second one burns out that you’ll notice.