What Causes the Hazard Lights to Work but Turn Signals Not to Work?
2 Answers
This situation is generally caused by two reasons: either the flasher relay is damaged, or the turn signal fuse has blown. The former can be replaced by yourself, while the latter requires careful inspection of the turn signal circuit for any short circuits before replacing the turn signal fuse circuit. Checking the Relay: Check if there is power at the live wire terminal of the flasher relay. If there is no power, inspect whether the wire to the power source is broken. Connecting the Terminals: Use a screwdriver to connect the two terminals of the flasher relay. If the turn signals light up, it indicates a fault with the flasher relay, which should be replaced. If they do not light up, inspect the flasher relay. Open the flasher relay cover and check if the coil and resistor are intact. If the resistor heats up but the contacts cannot close, press the movable contact; if the turn signals light up, it indicates a relay fault. Adjust if the contact gap is too large. If pressing the movable contact to close the contacts still does not light the turn signals, use a screwdriver to short-circuit the contacts. If the lights then turn on, it indicates oxidized contacts.
I've seen quite a few cases where the turn signals don't work but the hazard lights do in cars that have been driven for over a decade. The most likely cause is burnt or oxidized metal contacts inside the turn signal switch, preventing the signal from the steering column lever from getting through. Sometimes, a partial failure in the turn signal function of the flasher relay can also cause this, even though the hazard lights still work. Another possibility is that the turn signal fuse has blown individually, which can be checked in the steering column fuse box. Additionally, loose wiring connections causing poor contact are a common cause, especially in the densely wired area under the steering wheel. Since turn signals are crucial for driving safety, it's important to promptly visit an auto repair shop to diagnose the issue when this happens. Never risk driving under such conditions to avoid rear-end collisions when changing lanes.
