2016 Fiesta electrical fun

Hi, i have a 2016 Fiesta SE hatch that has been pretty trouble free. However a few electrical quirks have shown up and I’m trying to figure out where to start.

Here’s a list of what’s been going on.

  • a couple weeks ago i noticed the radio/CD cutting out for a second or two at random times.

-sometimes when I’d park it’d say “traction control off” even though i never changed the setting and it was still on.

-Normally if i have the radio and turn the car off, then open the door the radio shuts off. Sometimes after i open the door the radio will go off and then on for a second before shutting off for good.

-twice I’ve gone to start and all dash lights go on like normal but no start. Turn the key back and try again and it starts.

No CELs. New battery in December and no corrosion on the terminals. What should i try or check?

Idk either but you might start looking for a new or used body control module.

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The “Traction Control Off” indicator could be caused by something abnormal the computer has detected that it thinks may affect the car’s drivability. That function requires everything in the engine,transmission, & brakes be working properly.

BTW, why do you think the traction control remains on, even though the indicator says it is off? The reason I ask is b/c if it is on when it shouldn’t be, that could be unsafe and must be addressed immediately. That would be the first priority for this set of symptoms imo.

If I had this set of symptoms the first test I’d do as a diy’er is measure the battery voltage. It should be about 12.6 volts first thing in the AM, before starting the car. Then immediately after starting the engine it should be in the 13-15 volt range.

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New battery in Dec. It still would not hurt to have it checked because one going bad that soon is rare it does happen. If it checks good then you might want to pay for a diagnostic then decide what to do.

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Basically Traction Control is automatically on just like the ABS is always on, the button on the dash (or infotainment center or wherever) only deactivates the TC so it does not work which in return gives you the ability to spin the tires (stuck in snow/mud etc), or in other cases allows you to spin the tires while off the ground for whatever reason…

I would use a scan tool to look for pending codes also… Other than that, I would be throwing darts at a dart board hoping one would stick…

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Thanks. I’ll tinker around a bit. One thing I did see was how to do a BCM reset and I’ll give that a try first. Basically removing both positive and neutral on the battery and touch the connectors. (Not the terminal)

Just to add. the traction control is not the light on the dash, but rather shows up on the radio display. One came on briefly this morning. Something about climbing a hill. While driving downtown.

My advice, don’t do that. Just wait a few minutes for the residual charges to dissipate on the various control boards.

Most control electronics are isolated from the main bus voltage coming from the battery. When you short out the main battery terminals, you only discharge the input bus capacitors. This rapid discharge is not good for those capacitors. Secondly, where there are voltage regulation circuits, the input has capacitors and the output also has bus caps. Shorting the input creates an abnormal condition where the output caps are still charged and the input caps are not. In a design where they left off the reversal diodes, this can cause a backflush of energy in the wrong direction through the regulator, damaging it or other circuits.

Can you get away with doing this? Probably. But why take the risk? The individual board supplies will dissipate by themselves fairly quickly so you only save a small amount of time at the risk of damaging some electronics that may be expensive to replace. My2c.

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Thanks, so maybe just try disconnecting the battery for a minute and reconnecting? No touching connectors?

Disconnect, walk away for, say, 10 minutes.

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You could disconnect, eat lunch, then return and reconnect the battery. Maybe @TwinTurbo knows how long it takes for the capacitors to discharge and can offer better advice. I’d rather have the terminals disconnected too long. If the time off power isn’t long enough and the problem persists you won’t know if the reset was effective or not.

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Thanks. I’ll give that a shot this afternoon.

But before you disconnect anything, how about checking for (pending) code(s) with a scanner, it is free at most auto parts stores… May not be anything there, but doesn’t hurt to check…

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Thanks. My daughter has one. I’ll ask her to bring it over.

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