nI have a 2004 Toyota 4Runner that the left front blinker is blinking fast and not working. All the other blinkers in the car are ok. I replaced the bulb and it is still not working. What do I need to replace?
Bulb out = less load on the flasher circuit and will increase the speed of the flasher. You still have a problem with the bulb or socket. Clean out the socket with an electrical cleaner or spray and then put a small amount of dielectric grease on the termination points. You may have to bend the tabs out a little in the socket with a small screwdriver if there is a bad connection to the terminals on the bulb.
Above answer is great, 99% of all electrical problems are caused by bad connections. If that's not the problem you must trace the wiring and look for bad spots (broken insulation resulting in wire corrosion, etc.)
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