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Q: Both turn signals stopped working at the same time

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I was driving home from the other day in my 2006 Ford Fusion when my turn signals suddenly stopped working. I previously had problems with the handle not staying in position until the car has turned, but I just held the handle in place a second longer and that did the trick. This was a totally different problem. Assuming all the bulbs didn’t just go out at the same time, what would cause the turn signals to totally stop working?

A: It seems everywhere we look in the digital ...

It seems everywhere we look in the digital age, a computer is performing a job or task that used to be carried out by conventional means. In the case of your turn signals, what was once a simple fuse box is now called a “Smart Junction Box”. The SJB is responsible for receiving requests from the driver, and performing tasks that are associated with the command. In older vehicles, when the driver (You) moved the turn signal lever, the switch physically connected the related circuits and voila - there was light! Now, when the driver (You) moves the turn signal lever, you are sending a request to the SJB (HAL) for light activation. If the SJB (HAL) decides that any parameter is incorrect, or if HAL experiences a catastrophic failure, the lights remain off and you turn at your own peril. Each year, it seems more and more functions are integrated into these modules, and as a result, more failures become prevalent.

While these failures are fairly common, it would be wise to have a technician confirm this is the case. I strongly recommend having the vehicle inspected by a qualified technician with a diagnostic scan tool. The technician can then retrieve any potential trouble codes, perform output tests, and confirm that all of your turn signal bulbs did not in fact decide to go on strike. If SJB replacement becomes necessary, costs can vary widely because reprogramming at the dealer is typically necessary. In any case, proper diagnosis is crucial. As an aside, it is very possible that your previous concern of the turn signal stalk not holding position will still be present, and may have to be addressed with the physical switch being replaced. Once again, the technician can make that determination on site.

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