2000 Windstart Alternator Smart Charge 14.7v @start, 12.5v after 30 minutes

[phil-l]

Tom -

Wow! You've done a lot of research.

I must admit that I'm not familiar with the silver-calcium battery issue. So we're all up to date, here's some info from Wikipedia:

Silver Calcium alloy batteries are batteries with a water-acid electrolyte, but with grids made from calcium-silver alloy, instead of traditional lead-antimony grids. They stand out for its resistance to corrosion and the destructive effects of high temperatures. The result of this improvement is manifested in increased battery life and maintaining a starting power over time.

I see some interesting Ford of the UK specific info here (page 9):

http://www.partinfo.co.uk/files/All%...0Batteries.pdf

I've replaced my Windstar battery with aftermarket brands, using both Die Hard and Duralast over the years. I've never seen mention of silver calcium issues for aftermarket batteries in the US.

More reading to do...

[MrCreosote]

Yeah Phil,

I'm really disappointed with the lack of anyone solving this problem on the internet.

I guess I'm trying to make this thread the World's Best Collection of SCS malarkey.

DISCONNECTING the 3-WIRE CONNECTOR:

What is interesting is that one outfit said only remove the 3-wire connector when the engine is off. If I do that, my alternator will not charge at all when I start the engine.

So do I have a bad alternator or is that bad advice?

UNCONTROLLED ALTERNATOR:

The Regulator Chip reference shows how the PWM offsets this "sawtooth modification" of the Regulated Charge Voltage.

I still am looking for any way to simply mod the alternator to run at an Old School fixed voltage. (If it would have run at 13.9 w/o the 3-wire, I would have left it hanging and decreed problem fixed!)

VOLTAGE DROPS:

But I do know I've got voltage drops in the system because of the difference between the cigarette lighter and the battery posts.

I really think the alternator is good, however it might be possible that its "smart" regulator might be degrading.
_________________________

I'd just like to see ONE PERSON say they fixed their problem. Since there is nothing out there that I can find, sounds like they simply 1) never fixed it, 2) sold the van, or 3) took to Dealer and never reported back. But I doubt 3) since if they took all the time to make a thread, they would be likely to post Problem Solved!

Still a bleak situation for us SCS guinea pigs.

[phil-l]

Tom -

Can you share *exactly* how and where you measured the voltage drops you're seeing? I'll try duplicating them on my van and share the results.

Phil

[MrCreosote]

The big problem was comparing the voltage across the battery terminals (not the posts) and comparing with the cigarette lighter which I am using to measure voltage with my DMM.

About a 0.3 to 0.4v drop.

When I turn on all the accessories, in particular the hi fan and the brake lights (go figure, they REALLY seem to kill voltage), I would get a drop of about 0.1 at the terminals and 0.3 at the lighter.

That suggests there is definitely resistance somewhere in the wiring.

I did a quick check from the post to the terminals (battery clamps) and didn't seem to see anything of interest.

I measure from the negative POST to the alternator case and got basically no voltage drop. Also to the little ground wires that are bolted to the top of the front fascia - one on each side.

So that should have eliminated any engine to chassis ground straps.

[MrCreosote]

Local specialists said the dash electronics runs about 0.3v lower than battery so my cigarette lighter voltage drop is exactly what it should be.

Frankly, I have found no evidence of a bad voltage drop.

The fact that the charger starts at 14.7v and slowly declines to 12.2v indicates that the SCS is actually doing what it is supposed to do - reduce voltage as the battery warms up.

The problem is that it is "getting the wrong answer."

The only thing it knows is battery voltage and air and water temperature.

So my guess is a temp sensor OR the ECM is bad.

Or it could be the VR in the alternator is losing its "calibration" and interpreting the PWM improperly.

So it could be:

1. Alternator
2. Temp Sensor
3. ECM

The local experts charge $65 an hour to diagnose and will tell you the problem and an estimate. They said you are free to DIY or let them do it since they get paid their $65 for their work.


Might be worth paying the labor to get the diagnosis. But they want $204 for a top quality Bosch remanufactured alternator.


And I do know that cheapo Chinese alternators can blow VR's like popcorn.

[12Ounce]

I've never been aware of the PCM controlling the alternator in any fashion. I thought the alternator was just a current generator supplying up to its rated current limit at near 14 volts ... all the while, the voltage and current control being internal to the alternator.
.
At 375K miles and being 15 years old ... I just can't allow this thing to become so sophisticated... and requiring more attention. (LOL!)

[MrCreosote]

12ounce,

If you have an earlier Windstar, you might just have a conventional charging circuit.

The SCS (Smart Charge System) has a 3-wire connector on the top of the alternator in the rear. These are 3 small signal wires.

If you have that, you are screwed.

But everyone is screwed since ALL cars have gone to these kinds of systems for tweaking CAFE, emissions, and maintaining constant engine idle speeds.

I am being crushed here with another small snow storm - just a couple inches - and the roads are almost unnavigable. Its one of those light powder snows that puts down 1" in 6 hours but NEVER stops. No salt here too. And not budget to pay the plow drivers.

[TheBackyardDIYer]

OK, I've been trying to follow this thread as best I can...some of it I understand and some I don't. I recently had my codes pulled and got a B1318 (low battery voltage I think) and was wondering if it has something to do with this system or just a bad battery (or wrong battery after reading this thread). The other day I put a voltmeter on it and before starting it was 12v exactly. After starting it was 13.2v. Under load (a/c on) 12.7 then up to 13.2v. After turning the van off (ran for about 1-2 mintues) 12.3v. It doesn't even sound like mine is going as high as yours, but it was also about 30 minutes after I had driven it, so maybe it was still warm from before, thus not so high voltage?

So a couple of questions...

1) How can you determine if you have a Silver Calcium battery? I read also another forum (which I can't find now) that lead-calcium would work also, just not the lead antimony...any ideas on that? I have looked at Auto Zone online and I don't see anything that says whether it is "silver calcium" or not.

2) How can you determine which problem you have (Alternator, Temp Sensor, ECM)? Will a simple alternator test at Auto Zone still determine if you have a bad alternator?

I plan on taking my battery and alternator and getting them tested in the next week or so...we just got hit with that snow storm you are getting hit with. We got 7" of snow where I live and that just doesn't happen around here. It usually doesn't even snow...

[MrCreosote]

I don't think the Silver Calcium battery is used on the Windstar. The SCS talk is highly Ford Focus and UK related (international too - Ford sells completely different stuff outside the USA)

Check you voltage when you start first thing in the morning - you should get your 14.7v if its like mine.

Then as you drive it, the voltage will slowly droop down to 12.5 after the better part of 1 hour.

You will see definite reductions each time you shut the engine off for 5-10 minutes and then restart it. I think heat soak gets into the temperature sensors, makes them higher, then the ECM thinks the battery is hotter and reduces the voltage.

For example, I was running around town doing quick errands I got something like the following each time I restarted the engine: 14.7, 14.3, 13.9, 13.7, 13.5, 13.2,
12.9, etc.

FYI, BOTH temp sensors cost less than $20 total from Rock Auto. I think I am going to change both of mine since I have always suspected they might be reporting low since I think it takes too much time to warm up and go into OD lockup.

Of course, if they were reporting too cold, the ECM would demand a HIGHER voltage. To get a LOWER voltage result, the temp sensors would have to indicating TOO HIGH a temperature.

So now I'm thinking it is either the ECM or the VR in the alternator.

So it could still be just an alternator.

The local shop, Murray Electric, is where they solve all these problems. I can get a full diagnosis for $65 an hour and they said they never take more than 2 hours to find the problem. I just might make an appointment and simply wait while they do it.

But it sounds like we have a lot more snow coming. This is REALLY stepping on my LAST NERVE!

[MrCreosote]

I don't know how sophisticated they can test an alternator.

They would have to supply a PWM signal to control the output.

The test where you pull the 3-wire connector and should read 13.9v output where the alternator is now running like an old one - off the fixed voltage VR.

Even if the alternator was "out of calibration" and produced less or more voltage given a PWM signal, the feedback 12v to the ECM would result in a correction of the signal to the alternator to get the desired voltage.

Another thing, when you put a load on the system, the voltage will drop and then should slowly recover. The purpose of this is to NOT shock the engine and cause the rpm to drop quickly - this has a bad effect on computer controls.

Mine does NOT RECOVER! You put the big load on it and it never comes back.

So that is a problem that I have.

THEORY:

1) The ECM is controlling the alternator because the voltage "set point" changes with time.

2) But the voltage does not recover after a big load is dumped on the system. This means the ECM is not doing its job.

NOTE: One of the tests is that there is a PWM signal sent to the alternator and then a reference square wave sent to the ECM from the alternator. A Diagnosis is that the reference signal must be constant no matter what load. If it varies like the signal, then the VR in the alternator has failed.

This failure, intuitively sounds like it would interfere with the operation of the system because some delta between the two signals has some meaning in the system.

Even if the correct battery voltage is available at the ECM, evidently this delta error will screw things up.

The delta may provide the alternator load to the ECM.

So if the delta is always zero due to failure, the ECM thinks there is no load on the alternator and no voltage adjustment is necessary.

This could explain why mine does not recover after a load is applied.

GOSH, I wish I had a little hand held scope. I have big clunky Tektronix and BK Precision lab scopes which are well, big and clunky.

I guess you could do Sudoku or SCS for entertainment.

[TheBackyardDIYer]

I had to go back and re-read the whole thread again to make sure I am keeping up and understanding fully. It sounds like you may have it about tracked down. If you hook it up to that big, clunky scope of yours, maybe you'll know for sure? I have never used one and the information on this thread is the first I have ever heard, so that is as far as my knowledge carries on that...

Like you say, since your voltage is dropping as you drive (but starting at 14.7), the SCS seems to be trying to work, however, not going back up seems as though it would have to be the PCM sending the wrong signal or no signal at all...too many variables.

On one of your earlier posts, it said, "During driving, the charge control lamp is only switched on if the PCM detects the following faults: Impermissible voltage, Internal alternator fault, Communication fault PCM/alternator." I suppose the "charge control lamp" is the dash light...I haven't seen anywhere if you said that you getting that light on? It seems as the couple of problems you are indicating would trigger that light? Best thing to do would be to put it on a scope and see what you got...

As far as the Silver Calcium battery, why would the battery only need to be on the Focus which has the SCS as does the Windstar? Although I can't really find anything that lets us know...Like you said, EVERYTHING dealing with the SCS or Silver Calcium is either Focus related or in the UK. It would seem that if the Focus needs it for the high initial voltages, then others would as well...I suppose all batteries will work, just not as long.

Sorry this probably doesn't help, but it has been buggin' me all day. You seem very determined to try and figure this out, and I would like to know as well.

[MrCreosote]

FIRST, my Idiot light has never come on.

This is actually quite bad because that light is controlled by complex electronic circuitry that actually thinks the alternator is OK.

I believe somewhere earlier in this thread the Lead Acid battery charges at 14.0 to 14.4 while the Silver Calcium is 14.4 to 14.8

What is suspicious is that system charges at 14.7 when cold.

What is interesting is how the ECM might be controlling the alternator.

A stupid VR simply adjusts voltage to match some set point.

The ECM has the battery voltage availabe yet this is not enough!

While the ECM sends a PWM signal to the alternator it also requests the return fixed width square wave from the alternator!

Why?

I can see 2 other potential variables the ECM wants:

• Alternator load, or
• Alternator integrity of internal electronics

Who knows what the ECM does with the alternator "reference signal" which is supposed to be constant?


Maybe it does a Difference between the PWM signal and this Reference?


The Cooper info described a failure mode where the Reference becomes identical with the Signal.


A GREAT QUESTION: What are the symptoms when the Reference = the Signal?


ALSO: while I don't have any check engine lights on, I should check to see if there are any codes from the OBDII port.

[TheBackyardDIYer]

The "idiot light" not coming could be another indicator of a faulty PCM?

Seeing as how the voltage when you start the van cold is 14.7v, then it is registering the input that is required to begin the SCS process...thus, like you said, the PCM is receiving info from the sensors or alternator (whatever it is exactly that triggers it). As the van warms it slowly goes down like it is supposed to, indicating that the sensor info is probably correct?

Have you done this: "Next pin 1 & 2 need checking back to the PCM for resistance, isolation from ground and each other. If ok, its out with the scope." I suppose if they show to be in circuit with one another (suggesting an internal error) that would indicate that the wave pattern would be the same?...thus needing a new alternator.

However, as I was reading, I got to thinking, everything seems to work properly until you add a load and then the voltage never recovers. Pin 2 is the signal to the alternator of a load...when the load is added the wave pattern changes and the PCM tells the alternator to compensate. If you aren't getting that PCM request to compensate for the lost voltage, then the PCM is probably faulty (or bad wire?).

Maybe that "reference signal" is just to let the PCM know the alternator is functioning at all? And also, the post you put in earlier says that if the "reference signal" does't match battery voltage, the SCS will drop out. Which I don't expect this to be a problem as it seems that your SCS seems to try and function properly.

It seems to come down to the SCS part of the alternator or the PCM. Put the scope on it, quit driving yourself nuts, and check it! Or pay the other guys to do it...

I did the test on mine this morning when I went out. I got 14.84 volts at start up...drove to McDonalds and back, which is about 4 miles round trip and it didn't decrease hardly any by the time I got back...I think it was about 14.7 or so...I haven't really driven any more today to check.

[MrCreosote]

I was thinking what the expert tech said, to not use the cigarette lighter to measure voltage.

He said the dash voltage is 0.3v lower than the battery which I measured.

Now what is interesting is that with big load applied, the dash drops say 0.3v while the battery only drops 0.1v

So the dash voltage (cigarette lighter) drops according to load.

But the battery is being regulated.

So like the tech said, take your measurements off the battery.

I remember doing a cursory check of battery V when I applied a load and I simply don't remember what it did. Could have been not much of a drop like 0.1v and not the 0.3v from the dash.

[TheBackyardDIYer]

I suppose the dash could drop more because the voltage has more resistance to travel through as opposed to the battery...same as the reason the voltage is 0.3v lower already at the cigarette lighter. And I guess the load in the dash makes sense because when a heavy load kicks in, the dash lights flicker (at least on my van...)

So am I clear that you have a problem still with voltage not coming back up after a load is applied. Although, if it is only dropping 0.1v you can't expect much of a change. Or have we come to the conclusion your system is working properly?