dash battery light makes alternator work? my 4.9 conversion using Ed's harness----when the key is turned on the battery light does not come on and other forum members tell me this is very important. symptoms---car runs well when the battery is freshly recharged but then deteriorates after a while running------battery requires recharging every time-----the alternator supposedly tested out fine ??????? Please help
IP: Logged
05:20 PM
PFF
System Bot
jstricker Member
Posts: 12956 From: Russell, KS USA Registered: Apr 2002
As you can see, it is required and in fact is the circuit you "break" when you do the IAC motor learn procedure. Hope this helps. BTW, our harness from Ed's lights up the indicator just fine on GT gauges, so you might check your wiring from the connector on forward since something is wrong there.
John Stricker
IP: Logged
05:50 PM
Vonov Member
Posts: 3745 From: Nashville,TN,USA Registered: May 2004
What?? You dint believe me?? Ohhhhhh, Panchoooo....lol, all right!! I found this on Google...
"Now we all know why it is called an IDIOT LIGHT! I came across something that all GM owners should know about. One of my neighbors came over to seek my advice on a baffling problem he was having with his GM (I think it was a Chev) and its charging system. He was having dead battery problems (sort of like Don was in another story) and had taken his alternator off to replace it. Fortunately he had taken it to "Wheels" the former National Auto store, and they had tested it on an alternator testing machine. There was nothing wrong with it. This neighbor, I'll call him Artie, had the foresight to do some diagnostics ahead of time and determined that there was no output (14.5 volts) at battery or at the alternator stud, so a logical conclusion was that the problem was in the alternator - it has a built in voltage regulator so logic prevailed. Replace the alternator and solve the dead battery problem, right? Nope.
I walked over to see what I could see. We had the service manual open to the circuit describing the charging system. I traced the wires and determined which one was the field and which was the bat and which one was ground. Then I noticed something strange. I thought it was a typo - the wire from the 12 volt source to the field winding went through the idiot light filament, that's right, the bulb is in series with the field supply. Alternators don't have a true field supply like the old generators had with external voltage regulators which regulated the output by switching the field winding on and off. But they do need something to start the system working. Once the system is putting out its current the system becomes sort of self sustaining.
I took a short length of wire and connected it to the field terminal while the engine was running. Suddenly, the voltmeter across the battery went to 14.5 volts! I took the wire off the terminal and sure enough the system continued to charge at 14.5 volts. Fixed, right?? Nope.
Artie shut the engine down and restarted it again - nothing - jump the field, 14.5 volts.
I asked Artie if the idiot light was on while it was running and not putting anything out. Nope. He shut it down again and we tried it all over again, only this time I sat in the driver's seat and Artie did the jumper thing. Same results, only I did notice something strange. "Just where is the "alt" idiot light on the dash panel Artie? I didn't see one - just an engine light and an oil pressure light."
There was no idiot light for the charging system! I took a flashlight and held it at an angle to the dash panel. There, not visible under normal lighting conditions, was a place for the "bat" light. Yet it did NOT light when the switch was turned to the "ON" position. Then it hit me like a ton of poop! Remember I thought that the circuit diagram was in error - that the idiot light was shown to be in series with the field terminal on the alternator?? Well, that was not a typo! The bulb in the dash panel is part of the charging circuit. It is REQUIRED to be functional to supply the initial field voltage to get the alternator started doing its thing. IF THE BULB IS BURNED OUT THE SYSTEM WILL NOT CHARGE!!
It took us another half an hour to get to where the bulb should be but it became obvious that it was going to take a LOT more than a half hour to replace the bulb. It looked like part of the instrument cluster was going to come out before we got to the bulb. Plan "B" went into effect. I found the wire under the hood that supplies the idiot light and wired in a small socket and a bulb under the hood. I connected the other end of the wire to the field terminal and started it up. Voila! Charged just like new. I taped the bulb and socket to a handy vacuum hose and closed the hood. To this day that GM product is still riding around with a bulb taped to the vacuum line under the hood. I would love to see the face on the mechanic who discovers that bulb and wonders what the heck it is doing there!!"
Whap!!! (slaps Jeff in back of head w/week old (unrefrigerated) mackerel)
------------------ 88 Formula, "Asphalt Aviator"
"I've seen em---they're little fellers. You know, the Artesians..." ---caretaker at Olympia Brewery
[This message has been edited by Vonov (edited 09-20-2004).]
IP: Logged
05:53 PM
jeffndebrus Member
Posts: 2772 From: Jacksonville, Fl- usa Registered: Aug 2001
Ok---I wrote to Ed Parks and he told me that we were supposed to build and use an energizer wire. Can someone please tell me how to do this as it sounds like this is the problemo----no energizer wire circuit thingy. lol
IP: Logged
06:01 PM
Vonov Member
Posts: 3745 From: Nashville,TN,USA Registered: May 2004
I'd do like dude in the story above did...find a terminal on the fuse block that's hot in the run position on the ignition (one of the accessories should do) and run a line with a small 12-volt bulb from there to the brown wire on your alternator connector, like in the schematic diagram posted above. Maybe put a 20 amp fuse in line there too.
See? Bit by bit, you're gonna knock down these problems. Treat it like an infantry assault---one objective at a time. Hooah!
Tony
------------------ 88 Formula, "Asphalt Aviator"
"I've seen em---they're little fellers. You know, the Artesians..." ---caretaker at Olympia Brewery
[This message has been edited by Vonov (edited 09-20-2004).]
IP: Logged
06:09 PM
jeffndebrus Member
Posts: 2772 From: Jacksonville, Fl- usa Registered: Aug 2001
IIRC, the way it was explained to me, the primary purpose of the bulb is to provide enough resistance through the circuit to prevent the field windings from behaving like a dead short and heating up during the starting cycle. It helps prolong the life of the windings. The reason the bulb goes out after you start it, is because there is no difference in the voltage potential from one side of the filament to the other. If the alternator stops working, the potential is enough to light the bulb. You could just wire a straight wire, but the alternator's life would be shortened considerably.
------------------ 88 Formula, "Asphalt Aviator"
"I've seen em---they're little fellers. You know, the Artesians..." ---caretaker at Olympia Brewery
It all depends on which alternator you have. The older GM alternators will "self excite" at 1750 RPM. They should have the excitement wire, but do just fine without it. The newer ones need the excitement or they will never charge.
IP: Logged
12:00 AM
jeffndebrus Member
Posts: 2772 From: Jacksonville, Fl- usa Registered: Aug 2001
Ok guys--- I am using Ed Parks wiring harness---which should be plug n play into the fiero harness and dash lights included. Except for one thing---he does not include an alternator energizer wire for some reason. We ran a red wire from the stud/nut on the back of the alternator to the fuseable link block near the battery and from there to the red terminal on the battery.
-- ED says to run a wire from the battery side of the starter solenoid to the stud nut on the alternator. I don't see where this will make any difference.--looks like I am screwed again.
IP: Logged
04:29 AM
Vonov Member
Posts: 3745 From: Nashville,TN,USA Registered: May 2004
...run a line with a small 12-volt bulb from a point on the fuse panel which is hot when the ignition is in the RUN position to the BROWN wire on your alternator connector, like in the schematic diagram posted above...
Tony
IP: Logged
04:44 AM
PFF
System Bot
GTDude Member
Posts: 9056 From: Keysville, Virginia, USA Registered: Nov 2001
The same thing will happen if you pull the check engine light bulb.
Phil
------------------ I am always available to help those that need help. Since my back injury, I cannot work on many of the aspects of the cars, but I can offer the knowledge of my 27 years as a GM technician. Bring the questions on................!
IP: Logged
07:41 AM
jstricker Member
Posts: 12956 From: Russell, KS USA Registered: Apr 2002
I'm not sure where your problem is but we have Ed's harness and we didn't have to run another wire to excite the alternator. The only wire you have to run is a heavy gauge wire (should be about an 8 ga) from the alternator charge post on the back of the unit to either the starter post or the junction block over where the battery normally sits. That's it. The rest is plug and play.
You said he doesn't include an "energizer wire" and I don't know what you have, but on OUR installation the harness had the correct metripak connector for the alternator that did have the proper wiring. The charging circuit is not that complex, it seems you're making it harder than it is. Get some decent, heavy wire and go from the terminal on back the alternator (takes a 13 mm wrench IIRC) and go to the main post on the starter with it. Plug the appropriate connector into the alternator and you're done with the swap portion of the charging system wiring.
Now if you've changed to other than the Cadillac style alternator, or have other charging system issues or wiring issues in the harness on the car, then you're going to have other problems until they're corrected, but if you're using the alternator that came on the engine from the factory that's really all you need to do.
John Stricker
quote
Originally posted by jeffndebrus:
Ok guys--- I am using Ed Parks wiring harness---which should be plug n play into the fiero harness and dash lights included. Except for one thing---he does not include an alternator energizer wire for some reason. We ran a red wire from the stud/nut on the back of the alternator to the fuseable link block near the battery and from there to the red terminal on the battery.
-- ED says to run a wire from the battery side of the starter solenoid to the stud nut on the alternator. I don't see where this will make any difference.--looks like I am screwed again.
IP: Logged
08:13 AM
jeffndebrus Member
Posts: 2772 From: Jacksonville, Fl- usa Registered: Aug 2001
John, I will cut and paste Mr Parks e mail to me here so you can read it yourself.
Jeff, use #10 gauge wire from starter solenoid (battery connection)....under engine oil pan....up front of the trunk side engine head and attach to nutted stud on back of alt.
This is the only wire NOT included in the wiring harness as we do not know if battery is going to be front or rear mounted. Most any other routing will have belt/pulley/exhaust manifold interference.
Certainly hope this helps and is the problem.
Ed Parks from The Fiero Factory 8710B Hwy 53 Toney, Ala 35773
IP: Logged
08:43 AM
jeffndebrus Member
Posts: 2772 From: Jacksonville, Fl- usa Registered: Aug 2001
I'm not trying to make this more difficult!!!!! I just want to drive this freakin car. That's all! I don't want to make it complicated--I don't want it to sit in my garage and take up space--I want to drive it---seems like a pretty straight forward non complicated goal to me. BUt the last time I drove it--it sputtered, it shook like a paint shaker, it had no power, it would not downshift, at one point it idled at 50mph, and upon entering my driveway just to add injury to insult it blew a tranny cooler line off and flooded the driveway with hot tranny fluid, as well as spraying the crap all over the engine bay---up out of the engine vent across the rear window and all over the trunk lid. I have had the alternator checked ---I have replaced the starter.-----I was hopeful that the energizer wire was the key----now I realize that it is probably not-since we already have a wire going from the studded nut on the alt to the hot block near the battery.
IP: Logged
08:52 AM
jstricker Member
Posts: 12956 From: Russell, KS USA Registered: Apr 2002
I think the tone of my post came out wrong. I didn't mean that you were TRYING to make this more difficult. I think that you've been beating your head against the wall on this for long enough that you're really getting frustrated and just focusing on one spot, the alternator.
You need to keep looking at other locations. You know, IIRC from your other posts, that the althernator charges when you excite it. That means that either on YOUR harness in the car, or in Ed's harness (hey, things sometimes get screwed up) you aren't getting a switched 12V to excite the alternator. Pull the plug and turn on the key. Do you have 12V on both wires? One should be switched (that's the one that comes through the BATT light) and the other not, IIRC. If you have 12V on both of those wires, and you have a good, 8-10 ga wire going from the charge post to the starter terminal (that's the LARGE post on the solenoid), you should have a charging system that works.
Now if for some reason you do NOT have 12V on both of those wires with the key on, you need to find out why by looking deeper in the wiring diagrams. If you need more diagrams, let me know and I'll try to look them up and post them for you.
John Stricker
quote
Originally posted by jeffndebrus:
I'm not trying to make this more difficult!!!!! I just want to drive this freakin car. That's all! I don't want to make it complicated--I don't want it to sit in my garage and take up space--I want to drive it---seems like a pretty straight forward non complicated goal to me. BUt the last time I drove it--it sputtered, it shook like a paint shaker, it had no power, it would not downshift, at one point it idled at 50mph, and upon entering my driveway just to add injury to insult it blew a tranny cooler line off and flooded the driveway with hot tranny fluid, as well as spraying the crap all over the engine bay---up out of the engine vent across the rear window and all over the trunk lid. I have had the alternator checked ---I have replaced the starter.-----I was hopeful that the energizer wire was the key----now I realize that it is probably not-since we already have a wire going from the studded nut on the alt to the hot block near the battery.
IP: Logged
09:10 AM
jeffndebrus Member
Posts: 2772 From: Jacksonville, Fl- usa Registered: Aug 2001
I'm sorry, John I think you are on to something. I removed Ed's connector from the alternator and tested it. Looking at the connector there is one larger terminal and two smaller ones-----the large one is hot---all the time---key off or on. When I turned on the key---I do not get power to either of the smaller terminals.
IP: Logged
09:25 AM
jeffndebrus Member
Posts: 2772 From: Jacksonville, Fl- usa Registered: Aug 2001
Let me toss in my comments. Jeff, the big post on your alt, how many wires do you have on there and where do they go? I beleave the wire Ed want you to have (or make sure you have) goes from the post on the alt to the big post on the starter.
I should not be commenting on this, I just changed out my starter and find out it was the battery. After 5 years I should have known.
Jack
IP: Logged
12:10 PM
jeffndebrus Member
Posts: 2772 From: Jacksonville, Fl- usa Registered: Aug 2001
Here, I have the alternator connector off and the tester shows power at the largest of the three terminals. *** no power comes to either of the smaller terminals on this connector regardless of key position.
IP: Logged
03:14 PM
jstricker Member
Posts: 12956 From: Russell, KS USA Registered: Apr 2002
On this alternator you have a total of FIVE (5) terminals (normally). Four of them are in the Weatherpak connector and the other one is a stud on the back of the case that is normally marked BAT. The stud needs the heavier gauge wire that is probably best taken to the main stud on the starter solenoid that your battery cable is mounted to.
Now for the other four.
If you look at your alternator OR if you are looking down into the connector, you will see 4 terminals. In order, as you're looking down into that connector, they are marked on the back of the connector IN THE ALTERNATOR they are marked P, L, F, and S. If you have any doubts as to which is which, that's the order they're in and the one marked S is a little bigger than the other three.
P is a pulse terminal hooked up to one pole of the stator. It is used on some engines as a pulse sender for a tach drive. Don't worry about that one for your use.
L is for the Idiot light. This one you do need to worry about. This terminal is connected internally to the voltage regulator and externally to the idiot light. When you turn the key on, 12 volts is sent out through the bulb (or a 510 ohm resistor in a Caddy IPC) and that's what excites the alternator and gets it charging. If it never gets 12 volts to that terminal the alternator will not charge. When the alternator detects an internal problem (that is, it ain't charging) it shorts this terminal to ground and that turns on your light (or activates the IPC if it's equipped that way) to tell you there's a fault.
F is used on some vehicles to indicate the duty cycle of the alternator on some vehicles and it's not used in our application
S is connected externally to battery voltage, that is direct to something 12 volts all the time, to monitor and sense the voltage to be controlled by the voltage regulator. I have one of Ed's harnesses here in the shop, not mounted in a car, and I just probed the S connector on the plug and it has continuity to the large ring on the red wire that is supposed to go to your main starter terminal with the battery cable.
Now, if you have the harness in, and the large ring with the red wire on the starter, and the battery hooked to the starter, and you do NOT have 12 volts on the S terminal in Ed's connector, call Ed because it should have and the harness may be defective. Make absolutely sure you have your harness in correctly and the red wire with the large ring is connected to the main starter solenoid lug.
To me, the only possible problems you can be having are:
1) Bad alternator 2) You're not getting 12 volts with the key on to the L terminal. 3) You have the wiring harness installed incorrectly so that the red wire with the large ring is not hot all the time 4) You have a bad harness.
Hope this helps.
John Stricker
Edited to add a Fiero Charging Wiring diagram. They are the same for all years except the '88s when they went to the CS alternator. You're looking for a brown wire in your connector if you're checking wires.
[This message has been edited by jstricker (edited 09-21-2004).]
IP: Logged
04:48 PM
jeffndebrus Member
Posts: 2772 From: Jacksonville, Fl- usa Registered: Aug 2001
Mr Stricker, thank you-----ok you are correct----the connector is marked. referring to the pics above I get power at the big stud on the alternator----when checking the plug connector- I get power at the S terminal but no power at either the f or L terminals with key on----in my harness connector "p" is there but has no wire going to it.
Does the power flow from the fuse panel back through the idiot light towards the L terminal when the key is on?
IP: Logged
05:09 PM
jstricker Member
Posts: 12956 From: Russell, KS USA Registered: Apr 2002
Yes it does. The light bulb takes the place of the 510 ohm resistor and excites the alternator. IIRC, the diode in the Fiero diagram is in the engine harness so it should be gone from your harness now as it's not required in the CS alternators. You need to find out why you don't have power to the L terminal, that's what's keeping your alternator from charging.
John Stricker
quote
Originally posted by jeffndebrus:
Mr Stricker, thank you-----ok you are correct----the connector is marked. referring to the pics above I get power at the big stud on the alternator----when checking the plug connector- I get power at the S terminal but no power at either the f or L terminals with key on----in my harness connector "p" is there but has no wire going to it.
Does the power flow from the fuse panel back through the idiot light towards the L terminal when the key is on?
IP: Logged
05:28 PM
jeffndebrus Member
Posts: 2772 From: Jacksonville, Fl- usa Registered: Aug 2001
I hope that I am on the right track. In the pic below-you will notice that I have removed the dash panel and am testing terminal # 6 brown wire with the key turned on and I am NOT getting any power here. I had also tested the continuity of the idiot bulb-which appears ok.
IP: Logged
06:01 PM
jeffndebrus Member
Posts: 2772 From: Jacksonville, Fl- usa Registered: Aug 2001
Well, plugging the connector in the pic above back in and testing the brown wire--I get no power with the key in the on position.----I also tested the brown wire coming out the back of the fuse panel close to the guages fuse----no power here either.
At this time my battery is getting very weak so I have disconected the cables and put her on the charger for the night.
If anyone has any ideas---I appreciate it very much.
Jeff
IP: Logged
06:40 PM
jeffndebrus Member
Posts: 2772 From: Jacksonville, Fl- usa Registered: Aug 2001
Ok, I'm a dummy I'm a dummy I'm a dummy I'ma dummy I'ma dummy I'm a dummy I'm a dummy
During the time I was testing the brown wire at the dashboard---I had left the connector off the alternator-----I'ma dummy I'm a dummy I'm a dummy I'm a dummy I'm a dummy I'm a dummy
IP: Logged
08:20 PM
Vonov Member
Posts: 3745 From: Nashville,TN,USA Registered: May 2004
Ok, I'm a dummy I'm a dummy I'm a dummy I'ma dummy I'ma dummy I'm a dummy I'm a dummy
During the time I was testing the brown wire at the dashboard---I had left the connector off the alternator-----I'ma dummy I'm a dummy I'm a dummy I'm a dummy I'm a dummy I'm a dummy
No you ain't No you ain't No you ain't No you ain't No you ain't No you ain't No you ain't You're just tired, frustrated, and human...now Daniel-san...BREATHE...in...out...in...out... Ok, what was the result AFTER you reconnected? (actually, don't think it would make a difference, should still have voltage, right, John?) No fuses blown are there? ------------------ 88 Formula, "Asphalt Aviator"
"I've seen em---they're little fellers. You know, the Artesians..." ---caretaker at Olympia Brewery
[This message has been edited by Vonov (edited 09-21-2004).]
Actually terminal F is used. This wire should be controlled by the ignition key. Most fieros do not have this wiring there. Put a 12 volt source to that wire and your alternator should turn on. I usually run a jumper wire from the fuse box. The fuse I use is C/H on the 84/85 models, Fan E on 86 and up. Depending on what year your Fiero is you may have to upgrade your fuse. The earlier models have a 10A fuse and the later models have a 20A fuse. If you have an earlier model I recommend that you upgrade to 20A. Hope this helps.
IP: Logged
10:02 PM
PFF
System Bot
tstroud Member
Posts: 527 From: Chariton, Iowa Registered: Feb 2002
Actually terminal F is used. This wire should be controlled by the ignition key. Most fieros do not have this wiring there. Put a 12 volt source to that wire and your alternator should turn on. I usually run a jumper wire from the fuse box. The fuse I use is C/H on the 84/85 models, Fan E on 86 and up. Depending on what year your Fiero is you may have to upgrade your fuse. The earlier models have a 10A fuse and the later models have a 20A fuse. If you have an earlier model I recommend that you upgrade to 20A. Hope this helps.
On CS series alternator you don't want to use the "F" terminal.
"P" is the pulse wire, not used in this application. "L" Is the Lamp wire which needs switched 12v with a resistor or lamp. It signals the alt to start charging. "F" is the field wire, not used in this application. "S" is the battery voltage sensing wire. It is supposed to be a separate wire going to the + battery terminal so the alt gets a clean reading of the voltage at the battery, not just the charging system voltage. It must get ~12 volts for the alt to charge.
When troubleshooting remember that when the alt is charging the "L" wire will produce 12 volts on it's own. That is how the light goes off, the "L" terminal is a ground when the alt is not charging and it is 12v+ when the alt is charging. 12v+ on both terminals of the light bulb makes the light go out.
On CS series alternator you don't want to use the "F" terminal.
"P" is the pulse wire, not used in this application. "L" Is the Lamp wire which needs switched 12v with a resistor or lamp. It signals the alt to start charging. "F" is the field wire, not used in this application. "S" is the battery voltage sensing wire. It is supposed to be a separate wire going to the + battery terminal so the alt gets a clean reading of the voltage at the battery, not just the charging system voltage. It must get ~12 volts for the alt to charge.
When troubleshooting remember that when the alt is charging the "L" wire will produce 12 volts on it's own. That is how the light goes off, the "L" terminal is a ground when the alt is not charging and it is 12v+ when the alt is charging. 12v+ on both terminals of the light bulb makes the light go out.
I thought this true at one time. After a lot of trouble shooting I found this to work on the CS alternators. I have a few people come to me with this problem with motor swaps. I ran down all the connections on there cars and found giving power to terminal F turned on the alternator. Even the wire adaptors that I buy to adapt the CS alternators to the early fieros only use Terminals S and F. Don't rule anything out because you believe it untrue. I can even be proven wrong from time to time. I use it as a learning expierence.
IP: Logged
11:07 PM
jstricker Member
Posts: 12956 From: Russell, KS USA Registered: Apr 2002
No, the F terminal is not used. It is only used in specific applications and is not needed to make the alternator charge.
John Stricker
Edited to amplify on this a little as it seemed pretty curt...........
I've put quite a few of these on and the F terminal can be ignored. The shop manual also says the same thing that if it's not using the application that requires it, it is not used. An alternator isn't magic, but it needs certain things and the design of the CS alternator is such that it has to have that initial excitation to get it charging but once going, it will keep charging.
quote
Originally posted by mypontiac2:
Actually terminal F is used. This wire should be controlled by the ignition key. Most fieros do not have this wiring there. Put a 12 volt source to that wire and your alternator should turn on. I usually run a jumper wire from the fuse box. The fuse I use is C/H on the 84/85 models, Fan E on 86 and up. Depending on what year your Fiero is you may have to upgrade your fuse. The earlier models have a 10A fuse and the later models have a 20A fuse. If you have an earlier model I recommend that you upgrade to 20A. Hope this helps.
[This message has been edited by jstricker (edited 09-21-2004).]
IP: Logged
11:09 PM
jstricker Member
Posts: 12956 From: Russell, KS USA Registered: Apr 2002
Yes, the wire from the BATT light will still have voltage with the key on and the connector at the alternator plugged or unplugged.
And you're also right, he needs to put the battery on the charger and get some sleep.
To test this, the connector on back of the instrument pod should be plugged in otherwise how will the BATT light get power with the connector out?
Look at the wiring diagram, it tells you which fuse to check and that's the gages (sic) fuse in the fuseblock. If your temp and fuel gauge work, the fuse is good. Check your bulb, replace it with a KNOWN good bulb even if it "tests" OK. Follow the wires back to the connector and see if you get 12 volts at the white/black multipin connector by the computer. One half of that is Ed's harness, the other half is the original.
One thing did just occur to me, though, and that is if you've had your instrument cluster out a few times the printed circuit plastic and/or the bulb holder may have been damaged and if it has been, then you're not going to get the power to excite the alternator. The BATT light has to come on when the key is on, engine off or you're simply not going to get the alternator to charge.
John Stricker
quote
Originally posted by Vonov:
No you ain't No you ain't No you ain't No you ain't No you ain't No you ain't No you ain't You're just tired, frustrated, and human...now Daniel-san...BREATHE...in...out...in...out... Ok, what was the result AFTER you reconnected? (actually, don't think it would make a difference, should still have voltage, right, John?) No fuses blown are there?
IP: Logged
11:15 PM
tstroud Member
Posts: 527 From: Chariton, Iowa Registered: Feb 2002
I thought this true at one time. After a lot of trouble shooting I found this to work on the CS alternators. I have a few people come to me with this problem with motor swaps. I ran down all the connections on there cars and found giving power to terminal F turned on the alternator. Even the wire adaptors that I buy to adapt the CS alternators to the early fieros only use Terminals S and F. Don't rule anything out because you believe it untrue. I can even be proven wrong from time to time. I use it as a learning expierence.
You are right, it does make the CS series alt charge when you power the "F" wire. The reason that makes it charge is because you are powering the fields directly and bypassing the voltage regulator. I 'm not ruling anything out but I learned this during the 5 years I rebuilt these things on a daily basis. Just trying to pass on what I learned and I think is correct. But hey, I could be wrong too. If so feel free to straighten me out.
IP: Logged
11:17 PM
jstricker Member
Posts: 12956 From: Russell, KS USA Registered: Apr 2002
Powering the field will make it charge but that's not the way it was designed to work. I can put a 12V alternator on a 6 volt system and it will work too, for awhile, until I start blowing light bulbs and having all kinds of fun problems.
I'm not saying that powering the F terminal is a good, bad, or indifferent thing. I'm saying that it shouldn't be necessary to make it charge.
Oh, and BTW, Ed's harness DOES have a wire going to the F terminal. Where it goes and what it does I've never examined, but the point remains that it shouldn't be necessary. Knowing Ed, his guy that makes these might be taking the belt and suspenders approach and pulling a switched power off something to power the F terminal as well so that if there is a bad connection on the L terminal, the alternator still has a shot at charging.
John Stricker
quote
Originally posted by mypontiac2:
I thought this true at one time. After a lot of trouble shooting I found this to work on the CS alternators. I have a few people come to me with this problem with motor swaps. I ran down all the connections on there cars and found giving power to terminal F turned on the alternator. Even the wire adaptors that I buy to adapt the CS alternators to the early fieros only use Terminals S and F. Don't rule anything out because you believe it untrue. I can even be proven wrong from time to time. I use it as a learning expierence.
[This message has been edited by jstricker (edited 09-21-2004).]
IP: Logged
11:22 PM
Sep 22nd, 2004
Vonov Member
Posts: 3745 From: Nashville,TN,USA Registered: May 2004
Bump...how's it coming, Jeff? I know how you feel; once, at Ft. Hood, it took me two weeks (problem was intermittent, which did NOT help) to find a servo problem with an FM tactical radio...when I finally DID find the problem, it resulted in a minor change to the Technical Manual for that piece of equipment because the circuit the problem involved somehow never made it onto the schematic!!! Even the grizzled old Russian sergeant running the shop admitted he couldn't have found it any faster, when I showed him where the problem was and then showed him the schematic diagram.
------------------ 88 Formula, "Asphalt Aviator"
"I've seen em---they're little fellers. You know, the Artesians..." ---caretaker at Olympia Brewery
