Question edited for clarity.
Question moved to sub category.
Great advice and education on Ford SJB from our professional auto technician and electronics guru.
Jeff Armer Mar 23, 2022
They normally flash fast when a bulb is burnt out . There is no flasher , SJB - smart junction box - fords BCM - body control module turns the flashers on and off .
Principles of Operation
The smart junction box (SJB) monitors the multifunction switch position by sending multiple voltage reference signals to the multifunction switch. When the multifunction switch is in the LH or RH TURN position, or the hazard lamp switch is engaged, that input signal is routed to ground.
When the SJB receives an input from the multifunction or hazard switch indicating a request for a turn signal or hazard lamps, the SJB then supplies voltage to the appropriate turn lamps.
Hooking up a factory or some other type professional scan tool to check for codes in the SJB would be the first step in a diagnoses for this .
B1499 Lamps, Left Turn Signal Failure If a turn signal is inoperative, Go To Pinpoint Test O .
If a turn signal is always on, Go To Pinpoint Test N .
B1502 Lamps, Left Turn Signal Short to Ground Go To Pinpoint Test O .
Test N .
B2282 Left Turn Signal Switch/Circuit Short to Ground Go To Pinpoint Test N .
Your best bet , take it to a qualified repair shop.
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Fast flashing though, check the bulbs and in particular, the marker bulb on the left side. And never use LED bulbs in a vehicle that wasn't made for them.
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Would you like to take a crack at this one Jeff. I told him, but he doesn't believe me. I remember that technical site with the guy who turned the headlights off inside the workshop to not blind another tech, and the problem on the scanner, or oscilloscope went away.
https://www.fixya.com/cars/t29867334-when_push_brake_chimes_go_off_or_turn#cmnt_0
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