2000 Explorer Alternator Battery Problems

[phouse]

What was the outcome?

 

[Blueraven]

So you guys are saying that Ford uses an none easy access light bulb as a circuit protector for something as critical as battery charging?

That's freaking nuts. That being said, I'm have battery drain problems so I guess it's possible the battery isn't fully charging, so I pulled out fuse 15 and put it back it.

I'll be shocked if this fixes my problem.

Blueraven

 

[sleepyhead416]

#15 fuse solved my charging probem. IT WAS'NT BLOWN

 

[jahzwolf]

Ignition Switch Terminal on Alternator

I have replaced a alternator and a battery only to discover the issue appears to have been a intermittent connection from the ignition to the alternator I terminal..

Jumpering 12 volts from the A terminal the regulator turns on the field without any issues now..(except i have to remove the neg lead on the battery when overnight or when i park as this turns on the field ALL the time draining the battery, i will have to find switched 12volts to jumper to the I terminal)

The symptoms were cold start no charging evidence by the battery gauge and removing the negative lead off the battery that would kill the motor. not to mention the lack of increase in any voltage using a meter when the motor was on and reved..

at times the light would go out and the battery gauge would show a increase in voltage, and removing the negative lead on the battery the motor would still run.

So what these guys are saying about the alternator light being the same circuit can cause your alternator NOT to turn on is FACT. As per the new alternator documentation the I lead MUST have at least 1V on it before the regulator will turn on the field...

My bulb was good, but I think there is a connection problem on the left side of the instrument panel as i have other lights out there now, i had measured > 1 volt (light on) on this terminal when it was failing and over 4V when it was working(light out).. so perhaps 1 Volt just isn't enough.. and the way filament bulbs go bad perhaps it changed resistance or some such nonsense putting the terminal voltage at the hairy edge of the regulator's turn on voltage.. not really sure.. but giving it 12volts turns it on for certain, and the manufacture of the new alternator shows that terminal switched 12volts.. so jumper that puppy before you spend any money..

Here is a good link to a schematic for the 2000 ford explorer charging circuit that shows the bulb and a resister in parallel with the bulb..

http://www.justanswer.com/ford/2m7ml-several-all-main-concern-right-now.html

the little schematic that came with the new alternator shows switched 12volts going to the same terminal that the schematic shows the bulb being connected to..

The idea the engineer who designed this circuit is that 12v switched thru the bulb and resister would drop voltage over the bulb turning it on and leaving enough voltage to drop over the regulator terminal to turn it on. then when the alternator put out some current the regulator must change the resistance on that I terminal and the voltage would rise on the other side of the bulb turning it off..

Since my dash has a battery gauge i don't understand why the engineer didn't just switch 12v right to this terminal.. but he or she didn't. and now a lot of older vehicles have this problem where the alternator doesn't ever turn on..

So i am off to find some switched 12volts so i don't have to keep opening the hood every-time i park the vehicle.. as i refuse to tear apart the dash for this problem.. just very very frustrated i spent so much money for such a poor design..

thought this might help others..

jumper that I terminal over before you buy a new alternator or battery for your problems and i will feel better ..

update.. found a engineering link on this 4g regulator that says to make sure you put a 60 ohm bulb in series with the I connector... to protect the resistor inside the 4g regulator..

cheers!

JahzWolf

 

[rego]

You didn't mention checking fuse 15 for loose fit. Everyone that has reported a loose fit in this thread owns a 2000 including me. I see you do too. By the way, I had wiper problems with the same 2000 and the problem was also a loose fitting fuse.

 

[jahzwolf]

the fuse was good, as the light worked fine..

I found a switched fuse and connected the I terminal to the fused sided of the connector and now the alternator works fine.

What i have noticed since i did this is that my belt seems to be slipping as i can watch the gauge now sometimes dropping until i did some belt dressing that since no drop in the voltage.

What i think may have been the real issue is this belt, and with that poorly designed circuit not turning the alternator back on as it is, I had no output for long periods of time.

So the other 'first' thing to do is to put some belt dressing on your serpentine belt in case yours is slipping ..

Jumpering over the I terminal on the alternator to a good source of switched 12v will insure the field is always turned on, or should be anyway, will help in diagnoses of your problem prior to spending the money on a new alternator or battery ..

wish i had done these two things first.. might have saved me some money..

the brushes were in bad shape on the alternator so i am glad i have a new one, and the battery was old, so i am glad i have a new one of those too..

but if you are seriously out of money, those two tricks and getting a old battery fully charged as a spare might help those of you out of work..

cheers..

 

[jahzwolf]

So turns out the re-manufactured alternator was bad.. intermittent.. i took it to the Orielly's and they tested it bad.. got a NEW alternator this time put a bulb in series with my switched 12v to the I connector and the light would light up until the alternator started up and then went out just like the dash light would do..

So far so good .. total cost 400 bucks new battery and new alternator.. still wondering if the old battery could toast the old and re manufactured one ...

but some how i doubt it, i think the 4g regulator chip was bad in both ...

 

[rego]

That's good info. Thanks for the update.

 

[Gabe96Explorer]

So turns out the re-manufactured alternator was bad.. intermittent.. i took it to the Orielly's and they tested it bad.. got a NEW alternator this time put a bulb in series with my switched 12v to the I connector and the light would light up until the alternator started up and then went out just like the dash light would do..

So far so good .. total cost 400 bucks new battery and new alternator.. still wondering if the old battery could toast the old and re manufactured one ...

but some how i doubt it, i think the 4g regulator chip was bad in both ...

DUDE... $400 for an alternator & a battery!?!?! Thats highway robbery bro!

 

[jahzwolf]

yah but i got a Red Top Gel battery.. going price for a outstanding battery like this.. i hear they last forever.. no more issues like shorting cells due to the flakes piling up in the bottom of the battery, or sulfating plates that need 120 hours of charge to bust it all off the plates..

The Alternator being new, insured that i don't have someone elses intermittent issues of a regulator or old brushes, bearings etc being sold as remanufacutured..

I know, i could have gone to a junk yard and washed out my old battery refilling it with new electrolite but these days i barely have the time to turn the bolts with the new job..

Guess it only goes to prove that less is more, and there is a way to make it no matter how much you make...

The good news is when i am done with this truck whoever ends up with it, will have a reliable truck that will last another 10 years.. just hope i get to keep it that long..

 

[SoNic67]

My "regular" battery is Energizer, still crancks well and has 2001 code on it. How much longer you need that gel battery to last to recuperate the difference in price?
And yes, a completelly discharged battery will damage the alternator (the rectifier diodes).
Always precharge with a battery charger. When you jump-strart somebody always connect the batteries via cables and don't start the "donor" car for 3-5 minutes (to let the good battery to precharge the bad one).

 

[jahzwolf]

i agree you can make the lead acid battery go a long time, and you can recondition them. the track record i have had with them are about 4-5 years.

The gel batterys are expensive now, with more popularity the price will come down.. one of the things i love about them is that you can mount them any direction without fear of the acid spilling out, and they don't smell bad like the lead acid batteries.. so you can move them inside the passenger compartment if you have the need to do so..

I still have my old battery i will recondition it and use it for other things, once i am sure it doesn't have a shorted cell in it i might even put it back under the hood and move the gel inside the car, run it in parallel.

If i have to live in my car it will come in handy with a inverter to run appliances like a microwave, or a heater, or other stuff..

having a good spare gel battery is very useful .. and i am willing to help defray the engineering expense by paying the higher price to help make them popular..

still waiting on the lithium ion batteries to make it to the shelves i will buy those too.. talk about a revolution in batteries.. those nano particles of lithium really make a difference

 

[eazuaje]

Well, the first time I had this problem I just replaced the alternator and wiring, I had just bought my truck and I assumed "as I'm buying someone else problem, I had to fix it well cause now it was my problem"; after that, the problem continued, my battery was almost always dead, I had to pop the hood everytime I parked and it was a PITA. I replaced the battery with a BOSCH S5 unit, replaced the voltage regulator in the alternator with a brand new one from Motorcraft, I also replaced the bearings and seals, connector and wiring again, fuse #15 too; I followed a wiring schematics posted here. Now I was sure I had fixed my problem, and it was fine for a few weeks, after that the problem started again; so I decided to replace the bulb in the dash, after that it has run well, it's being a couple months now with no issues.
Measured at the battery terminals Alternator sends:
(No beams, lights or A/C) 15.5v when accelerated, 14.5 when idle.
(High beams, Lights and full A/C ON) 15.0v when accelerater, 14.1 when idle.
I also feel the engine runs better now. The electrical gremlin is finally gone now!

Thanks for the usefull information posted here by each and everyone of you.
I used this as a resource for my DIY proyect. I have to add this fix to my list.

Eiber.