Charging System Service Now

[davekro]

Looks like you have aftermarket lighting installed on your vehicle.

Disconnect all aftermarket equipment and re-evaluate. Chances are the issue will no longer be present.

Lighting all OEM. Never touched a bulb. Curious what makes you think I have aftermarket lighting?

does this display and then go away, or does it stays on the whole time you are driving?

As long as you are getting 14V out of the alternator, the car should keep charge on the battery.

Warning and LOUD multiple chime comes on invariably 20 seconds after starting. The warning remains for as long as I drive 'unless' I hit the OK button on left side of steering column to make it go away (until the next restart). /

Sponsored

 

[FordTechOne]

Lighting all OEM. Never touched a bulb. Curious what makes you think I have aftermarket lighting?

Your signature says "DI Blue: CDC light bar"....

 

[davekro]

Your signature says "DI Blue: CDC light bar"....

Oh, the CDC (brand) light bar is the roll bar looking add on. It has a brake light that lights when the top is down. It has been on ≈ 5,000 of the cars 6,000 miles. The current problem just started last month.

 

[GT Pony]

davekro - maybe you have a weak battery, or the internal resistance is too high. You would have to get the battery load tested to find out for sure.

 

[davekro]

davekro - maybe you have a weak battery, or the internal resistance is too high. You would have to get the battery load tested to find out for sure.

My old convertible with old battery was drained dead more times than I care to admit (wife was notorious for turning on and leaving on an interior light). It always charged back up and ran fine. Granted it was a 2000 Chrysler Sebring vert, so did not have the diagnostics of modern day cars. Maybe the the Mustang's monitoring system has the sensitivity equivalent of a 120v GFCI, where a minuscule voltage variance activates a warning sensor. The Mustang was left for 2.5 days and found with a completely dead battery. I 'think' I must have left the interior light on (wife would laugh at that!). Anyway, I jumped it then at home put is on a 2 amp slow charge until full.

 

[GT Pony]

Maybe the the Mustang's monitoring system has the sensitivity equivalent of a 120v GFCI, where a minuscule voltage variance activates a warning sensor.

That's what I'm thinking. The battery might be slightly bad and the charging system can tell.

 

[paul123]

hopefully this isn't a software glitch

one thing you might try is load testing the battery. Take it to an auto parts store or mechanic, or buy a gizmo amazon. It will measure voltage drop when you turn over the motor. If you are lucky, the computer is complaining about that.

Another idea is to jump start the car, and see what happens. With a second car connected in parallel, the car shouldn't see any voltage drop upon startup. Be sure to do this properly.

 

[paul123]

... The Mustang was left for 2.5 days and found with a completely dead battery. I 'think' I must have left the interior light on (wife would laugh at that!). Anyway, I jumped it then at home put is on a 2 amp slow charge until full.

just saw page two after responding. completely dead lead acid battery is easily cooked. It might still work, but not to original specs. Still worth a load test to see if there is too much voltage drop when turning over the motor.

I haven't tested my car, but I suspect those interior lights don't auto turn off by themselves. Hopefully that's not the case. This is 2015 / 2016 after all. addle:

 

[FordTechOne]

Oh, the CDC (brand) light bar is the roll bar looking add on. It has a brake light that lights when the top is down. It has been on ≈ 5,000 of the cars 6,000 miles. The current problem just started last month.

Does't matter when the current problem started. The charging system is equipped with a battery monitoring system (BMS) and a charging system monitor. It takes time for those ammeters to drift out of specification to the point where a module flags it as a fault.

Aftermarket components are the #1 cause of electrical issues. Take your aftermarket brake light off, disconnect/reconnect the battery, and re-evaluate for the issue. Chances are it will no longer be present.

 

[davekro]

Does't matter when the current problem started. The charging system is equipped with a battery monitoring system (BMS) and a charging system monitor. It takes time for those ammeters to drift out of specification to the point where a module flags it as a fault.

Aftermarket components are the #1 cause of electrical issues. Take your aftermarket brake light off, disconnect/reconnect the battery, and re-evaluate for the issue. Chances are it will no longer be present.

Well, the aftermarket brake light is disengaged while the top is up, so that is the same as being disconnected. It does not get energized/lit, so the system should not be aware of it, right? Maybe I will drop the top tomorrow to verify the LED brake light still functions properly.

 

[Jimboy2]

Well, the aftermarket brake light is disengaged while the top is up, so that is the same as being disconnected. It does not get energized/lit, so the system should not be aware of it, right? Maybe I will drop the top tomorrow to verify the LED brake light still functions properly.

The system may still know the aftermarket light is still fitted. It's really worth taking it out of circuit to prove its not the cause. Would be a simple fault finding exercise

 

[paul123]

LED light should be very minimal current draw

Since the car battery was pulled all the way to zero at one point, I suspect the Charging System is complaining about the battery.

 

[davekro]

The system may still know the aftermarket light is still fitted. It's really worth taking it out of circuit to prove its not the cause. Would be a simple fault finding exercise

Unfortunately, it would be a PIA. I'd have to remove the roll/light bar, then pull the rear seat bottom (easy enough) and the passenger side rear plastic trim to get to the wiring and the top actuated pin switch.

LED light should be very minimal current draw

Since the car battery was pulled all the way to zero at one point, I suspect the Charging System is complaining about the battery.

This seems somewhat more likely as the culprit, though it's worrisome that the first dead battery is enough to make the system cry: "Danger Will Robinson, Danger!" every time the car is started. :doh:

From time to time I used to run the charger's desulfate function on my 2000 Chrysler from time to time. Any chance running that on this relatively new battery would have any positive affect in deleting the warning?

I had hoped a code would show in the OBDll system that I could delete (no codes). I wonder if there is an 'only Ford accessible' code that was caused by the system when battery went dead, and since the 'dead condition' is no longer present, the warning would not repeat if the hidden code was deleted?

 

[GT Pony]

Did you try disconnecting the battery for a few hours, then reconnect? Maybe something needs a hard reset.

 

[paul123]

Did you try disconnecting the battery for a few hours, then reconnect? Maybe something needs a hard reset.

I think he did this already

OP, next stop, your nearest auto parts, or auto repair, and get the battery load tested under an engine start. Any weakness in the battery will show up as too much voltage drop.

Sponsored