The vehicle is actually a Chinook camper built on E350---we have a knifeblade cutoff at battery for storage. The fast blink was resolved by replacing bulb but after awhile, it repeated the problem. Replaced again, had same issue. Almost seems like when vehicle has been driven awhile it fails, but then cooling off overnight blinker is fine again...for awhile. Brake light also seems to go out on that (passenger) side, but fronts seems ok. May be it's the multifunction switch (turn signal/high beam/etc.)?
My car has 83000 miles.
My car has an automatic transmission.
What you are describing sounds like a bad turn signal flasher. The flasher unit is an electrical unit that is usually located under the hood and is wired with the turn signal lights. This flasher sends short intermittent bursts of power to the turn signals by interrupting and completing an electrical circuit intermittently to create the flashing you are accustomed to seeing when the turn signal light is activated. When this flasher becomes faulty, you may notice the turn signal lights remaining solid or in some cases flashing very rapidly. In either case this usually indicates the flasher has failed. I would suggest having an expert from YourMechanic come to your location to diagnose and replace.
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