What causes the turn signal on the side mirror to stop working?
4 Answers
The reasons why the turn signal on the side mirror stops working are as follows: Relay failure: To understand why the turn signal is not working, first check if there is power at the hot wire terminal of the flasher relay. If there is no power, check for any open circuit between the wire and the power source. If there is power, use a screwdriver to connect the two terminals of the flasher relay. If the turn signal lights up, it indicates a fault in the flasher relay, which should be replaced promptly. Excessive contact gap: You can also open the cover of the flasher relay to check if the coil and resistor are intact. If the resistor heats up and the contacts fail to close, press the movable contact. If the turn signal lights up at this point, it indicates that the contact gap is too large and should be adjusted. Turn signal switch failure: If the turn signal does not light up, another possible cause is a faulty turn signal switch. Use a screwdriver to connect the hot wire terminal of the turn signal switch to the left and right light wire terminals separately. If the light turns on, it means the turn signal switch is faulty and should be removed for repair or replacement.
The turn signal on the side mirror not working is actually quite common – I often hear customers complaining about it in the shop. The most frequent culprit is a burnt-out bulb. Over time, the filament breaks, especially if water gets in during car washes or from excessive vibration on bumpy roads. Another possibility is a blown fuse. Just open the fuse box, locate the corresponding fuse, and check it. If it's blown, replace it with a new one. However, be cautious about wiring issues – a loose connector or aged/short-circuited wiring can interrupt the current and prevent the light from working. Relay failures are also not uncommon; if that little device controlling the lights fails, the light won’t function. I’d suggest trying to replace the bulb or fuse yourself first. If that doesn’t work, seek professional repair immediately, as a non-functional turn signal means others can’t see your direction changes, which is dangerous, especially on highways where it could lead to accidents. During regular maintenance, pay extra attention to the lights and keep the lens clean to prevent dust buildup.
My rearview mirror turn signal suddenly went out before, which gave me a scare. After checking, I found it was just a burnt-out bulb—a simple replacement with a new bulb fixed it, costing only a few bucks. If the light still doesn’t work, it’s likely a blown fuse; check the turn signal fuse in the driver’s side fuse box to see if it’s intact. Another possibility is poor wiring contact—loose or corroded connectors. Just remove the light cover and tighten them up. Occasionally, a faulty control switch could be the culprit, but that’s rare. A non-functional turn signal is really unsafe—I once had a friend who nearly got rear-ended because of it. After that incident, I became more cautious and now check my lights before every trip. I recommend not delaying repairs—either buy tools online and fix it yourself or spend a little at the 4S shop to get it sorted, avoiding roadside embarrassment and fines.
Having driven for half my life, I've encountered the issue of non-functioning rearview mirror turn signals several times. Usually, it's a minor problem: the bulb has burned out at the end of its lifespan, or a fuse has blown and can be easily replaced. Occasionally, it's a wiring fault, with loose or corroded connections causing poor contact. Although turn signals are small components, their failure poses a significant risk; others may not clearly see your intentions, easily leading to collisions, especially in rainy or foggy conditions with poor visibility. Once you notice the light is out, check immediately—first inspect the bulb, then use simple tools to test the fuse. If all else fails, pull over and seek help—don't push on driving. Safety comes first; prevention is better than repair. During maintenance, remind the technician to inspect the lighting system to extend its service life.
