Charging System Service Now - Argh

[ice445]

Well. AG battery received, fully charged, and installed. Did the BMS reset as well (non-Forscan method). Battery shows 13.2V across the posts. Car fires right up, voltage meter goes immediately to 15V... and, about 5 seconds later, the Charging System Service Now message pops on. Back to the drawing board.

Current behavior is consistent - message pops up a few seconds after starting the car and stays on. This is different than the behavior I had when the pigtail was bad. In that case, the message would go on and off several times per trip.

So, I guess next step is to get under the car and try to find connection issues at ground, at starter connections, or anyplace else I can find. Last option is to swap the alternator (which appears to be generating voltage just fine) in the hopes the voltage regulator itself is bad. Ugh.

I assume you already did, but check the alternator leads in the engine fuse box. Using a meter, see if you have any voltage between the box and the alternator (when the car is off). This is called voltage drop testing and can help identify of you have wiring or connection issues.

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[ChipG]

I assume you already did, but check the alternator leads in the engine fuse box. Using a meter, see if you have any voltage between the box and the alternator (when the car is off). This is called voltage drop testing and can help identify of you have wiring or connection issues.

I will check that, thanks.

 

[ChipG]

Does anyone know if there are aftermarket or OE alternatives to the factory alternator? That’s the road I want to try next time.

I'm also interested in this if I need to replace the alternator, since it's only a year old or so.

 

[ZX3ST]

If you have Forscan, run PIDs against the alternator command versus the feedback. The alternator feeds back The ECUs request. I don't remember the exact verbiage, but it should be fairly obvious.

I popped an alternator at Heartland Park. It was charging OK, but the command feedback wasn't reaching the ECU. Something internal. New alt fixed it.

 

[ChipG]

Well, car went completely batty today - voltage meter all over the place, up as high as 17V, center screen shut down, A/C shut off, AdvanceTrac shut off, windows wouldn't even roll down. I'm crawling around under it tonight to check for any loose grounds or connections, but I will likely have to try the alternator next. Any feedback on alternators? Ford's clearly don't last long, what about other brands, or remanufactured so at least they're cheaper to replace regularly?

 

[ChipG]

Options I can get in a reasonable amount of time:

BBB Industries reman - $206 (RockAuto)
Remy reman - $247 (RockAuto)
Ultima remain - $322 (can get tomorrow at local O'Reilly)

Powermaster 245amp - $412 (Summit)

Motorcraft - $465 (LMR or RockAuto)

 

[ice445]

Well, car went completely batty today - voltage meter all over the place, up as high as 17V, center screen shut down, A/C shut off, AdvanceTrac shut off, windows wouldn't even roll down. I'm crawling around under it tonight to check for any loose grounds or connections, but I will likely have to try the alternator next. Any feedback on alternators? Ford's clearly don't last long, what about other brands, or remanufactured so at least they're cheaper to replace regularly?

Just stick with motorcraft ones, the aftermarket stuff out there is even worse these days

 

[ChipG]

Seeing as Motorcraft lasted less than a year for me, I have a hard time seeing how much worse it could be. I'm going to try the Ultima - I'm sure all the remans are the same crap, but O'Reilly has a lifetime warranty on it, so maybe I'll just replace it annually for free...

 

[ZX3ST]

Did you try any other troubleshooting? Highly recommend you run the Forscan PIDs I mentioned earlier before just swapping parts.

I've not had good luck in other cars with aftermarket alternators. Unless you go with a specialty unit ($$$), all aftermarket electrical stuff I've seen for the past 10yr is junk.

 

[Angrey]

I've been running this alternator for some time and it was fine before I installed the AG battery. I've had multiple issues with a restart version of the AG and now the ATX30. The ATX30 seems to be fine most of the time, but every once in awhile I'll get some sort of BMS system fault or issue, but then it will be fine for some time. I'm just convinced that no matter what you do (Battery resets, Forscan changes) the lithium battery will always have issues on anything other than a track focused/limited use car.

I've actually considered just going back to a typical OE type battery.

NEW HIGH OUTPUT ALTERNATOR 300A FOR FORD MUSTANG 5.0L V8 MUSTANG 5.2L V8 M/T | eBay

Just FYI, the pulley on this is smaller diameter, so my unqualified guess is that it's a typical OE type alternator that's just spun harder to produce 300A. Can't speak to real longevity because I haven't put but a couple thousand miles on the car.

 

[ChipG]

I have hooked up Forscan, and (of course) the system didn't go wild when I did, but the error still pops up. I ensured the BMS was reset, and the battery showed a 90% state of charge. I found the Generator Voltage desired signal easily enough, which was steady at 14.56. I am not sure what signal would be best to see actual output, but I checked a bunch of system voltages (battery voltage, PCM voltage, etc.) and all read at around 14.8 or 14.9. Is there a good signal that would show exactly what the alternator is outputting, or is that gap a good enough sign of a mismatch? I also plan to try changing the battery type from conventional to lithium to see if that will change anything.

Angrey - if your theory is correct on that alternator, I'd be a little concerned about that for a tracked car. The engine is at high RPMs enough - overdriving the alternator with a smaller pulley seems like it might cook it faster, no?

 

[ChipG]

By the way, here's the AG install finished (and yeah, that brace is pretty dusty there underneath the battery cover!)

 

[Angrey]

I have hooked up Forscan, and (of course) the system didn't go wild when I did, but the error still pops up. I ensured the BMS was reset, and the battery showed a 90% state of charge. I found the Generator Voltage desired signal easily enough, which was steady at 14.56. I am not sure what signal would be best to see actual output, but I checked a bunch of system voltages (battery voltage, PCM voltage, etc.) and all read at around 14.8 or 14.9. Is there a good signal that would show exactly what the alternator is outputting, or is that gap a good enough sign of a mismatch? I also plan to try changing the battery type from conventional to lithium to see if that will change anything.

Angrey - if your theory is correct on that alternator, I'd be a little concerned about that for a tracked car. The engine is at high RPMs enough - overdriving the alternator with a smaller pulley seems like it might cook it faster, no?

Absolutely, an alternator only gets so many revolutions and with added rpm/output and heat, it reduces the lifespan. I need it because I'm running an aftermarket fuel system and stereo system, the lower output alternator works the battery more and reduces it's life. As with most things, there's no free lunch or answer to all prayers.

 

[ChipG]

I assume you already did, but check the alternator leads in the engine fuse box. Using a meter, see if you have any voltage between the box and the alternator (when the car is off). This is called voltage drop testing and can help identify of you have wiring or connection issues.

I didn't find anything, but to check, where exactly would you connect the meter? I tried between the alternator leads, between each lead and the positive battery cable attachment, and between each lead and several open pins in the box. 0V everywhere.

 

[ice445]

I didn't find anything, but to check, where exactly would you connect the meter? I tried between the alternator leads, between each lead and the positive battery cable attachment, and between each lead and several open pins in the box. 0V everywhere.

Sounds like you did it right. 0v is what you should see if all the connections are solid.

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