What to Do When One Front Fog Light Is On and the Other Is Off?
3 Answers
One front fog light being on while the other is off could be due to a burnt-out bulb, which would require replacement; it might also be the car's cornering light, not an actual malfunction, as the cornering light illuminates during turns. If one fog light is on and the other is off while the car is turning, this is a normal phenomenon. Relevant information about fog lights is as follows: 1. Fog lights generally refer to automotive fog lights, installed at the front and rear of the vehicle. Because visibility is low in foggy conditions, the driver's line of sight is limited. 2. Fog lights are divided into front fog lights and rear fog lights. Front fog lights are typically bright yellow, while rear fog lights are red.
I encountered this issue last time too - it's super simple! Most likely the fog light bulb is burnt out. First turn off the engine and disconnect power, then locate the faulty fog light position. For sedans you can usually see the fog light rear cover by squatting down, while SUVs may require lying down to operate. Unscrew the rear cover, pinch the connector to unplug it, then press the clip to remove the old bulb. Remember the bulb model (e.g. H11/H8) - you can buy the same model for about ten bucks at an auto parts store. If it still doesn't light up after replacement, check the fuse - find the corresponding fog light position in the manual. Once my friend's car still didn't light up after bulb replacement, turned out the socket was knocked askew by a tree branch causing poor contact. If none of these are the issue, it might be a broken wire, then you'll need a repair shop.
As a road trip enthusiast, I always check the lights before long-distance drives. For a single fog light not working, follow these three steps: look, test, and swap. First, visually inspect if the bulb glass has turned black. Use a multimeter to measure the voltage at the lamp socket - it should read 12V normally. If you don't have a multimeter, use a test light by clipping the ground and probing the socket's positive terminal; it should light up. If there's no power at all, check the corresponding fog light fuse in the engine compartment fuse box (the fog light symbol is marked on the fuse box cover). If that doesn't work, swap the left and right fog light connectors for testing. If the issue follows the connector, it's a bulb problem; if not, it's an upstream wiring or switch issue. Don't overlook connector oxidation - last year in Qinghai after heavy rain, my fog lights were intermittent due to verdigris on the connectors.
