What is the reason for the left front turn signal not working on a BMW 535
3 Answers
BMW 535 left front turn signal not working reasons and solutions are as follows: Flasher relay damage: Purchase a matching flasher relay according to the vehicle model. Turn signal fuse blown: Carefully check the turn signal circuit for any short circuits, then replace the turn signal fuse. Turn signal switch failure: If the turn signal does not light up when pressing the movable contact or when the contact is closed, you can use a screwdriver to bridge the contact. If the light comes on, it indicates contact oxidation; if the turn signal still does not light up, the turn signal switch may be faulty. Use a screwdriver to connect the turn signal switch live wire to the left and right light wire terminals separately. If the light comes on, it means the turn signal switch is faulty and should be removed for repair or replacement.
I've driven a BMW 535 for many years and encountered situations where the left front turn signal didn't work, which is quite common. The main reason could be a burnt-out bulb due to aging, especially since the filament in turn signals tends to break after prolonged use. Another simple issue is a blown fuse—check the corresponding 15-amp fuse in the engine compartment fuse box; if it's blown, replacing it should solve the problem. Additionally, poor electrical connections often occur, such as loose plugs or corroded wires from moisture; the BMW 535's circuitry is quite delicate and prone to vibration-related issues. Inspect the bulb socket for rust, and if found, clean it or replace the bulb. If none of these are the problem, it might be a relay failure or an issue with the body control module, requiring professional diagnostic tools. For safety, avoid driving at night and get it checked at a 4S店 promptly, as a malfunctioning turn signal can lead to accidents or fines. Regularly checking the lighting condition during maintenance can help prevent such issues.
As an enthusiast who frequently tinkers with cars, I believe that a non-functioning left front turn signal is mostly due to electrical issues. Besides a burnt-out bulb or a blown fuse, short circuits or open circuits in the wiring are quite common. The wiring harness of a BMW 535 is prone to wear and aging after prolonged use. Check the connection points of the light assembly; if the plug is loose, tighten it with a wrench. If you have a multimeter, measure the voltage—it should normally be around 12V. If it's lower, the issue might be with the control unit. Relays can occasionally stick and malfunction; try tapping it to see if it resumes working. If this happens frequently, it could also be due to a faulty voltage regulator in the alternator causing unstable voltage. Don't delay repairs—non-functioning turn signals are particularly dangerous in rainy weather or at night. I recommend taking the time to conduct a thorough inspection and also checking the right light to prevent the same issue. Nowadays, new cars come with diagnostic systems; connecting to an OBD scanner at a shop can quickly pinpoint the problem.
