Searched: FD alternator in FC
01-01-09, 08:39 AM
#26
Thought this might help.
Ok, so my idea that the alternator needs to sense what voltage is being produced in order to know how much more to make is not valid at all? Why would it go to 15+ volts when I don't have the dash wire at all? Is that the alternator working on full blast? I am not really interested in making the boost gauge work, and I can't test the power to/at the injectors at idle because the haltech has a shared positive... lol I am going to test the Volts down the power trail like you suggest.
hi mate,
sorry been installing these for years.
the charge circuit needs to be connected as well as this is what tells the alternator to start/stop charging.
failing to connect all the terminals will make for a not happy alternator and the reason for seeing 12.3 to 16 volt iregularities.
read here -
http://www.ausrotary.com/viewtopic.php?f=16&t=33676
see this problem all the time
with all terminals connected you should get around 14.7 volts straight up when first starting the car. then after a long drive it should settle at 14.1 volts. that is a happy alternator.
cheers
sorry been installing these for years.
the charge circuit needs to be connected as well as this is what tells the alternator to start/stop charging.
failing to connect all the terminals will make for a not happy alternator and the reason for seeing 12.3 to 16 volt iregularities.
read here -
http://www.ausrotary.com/viewtopic.php?f=16&t=33676
see this problem all the time
with all terminals connected you should get around 14.7 volts straight up when first starting the car. then after a long drive it should settle at 14.1 volts. that is a happy alternator.
cheers
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/fd-alternator-problems-809791/
01-01-09, 10:04 AM
#27
HAILERS
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I'll say I was wrong if a series five/six alternator works like the attached jpg says. It says the alternator initially gets it's excitation from the warning light circuit. That small voltage coming FROM the warning light TO the L terminal passes thru the Field of the alternator thereby exciting it, which in turn causes the alt to START working. From then on it HAS to be the regulator inside the alternator that is regulating the Field voltage.
That said, I have a series five alterntor in one of my cars outside. The Warning light stopped working because of the usual cold solder joints on the warning light assy (I proved this by pulling the plug off the CPU and grounding the Y/L wire going to the Warning Light assy and they didn't all light up as they should when that is done).
So, I can start that car up and looking at the RTEK/Palm, I see 13.8vdc on the Palm right away. There is no L teminal wire connected in essence because the plug is off the CPU. If I take a digital meter to the alternator the ouput voltage is in the 14.3 range, so the real output is 14.3 not the 13.8 on the Palm. A voltage drop due to the ECU doing *stuff* or working so to speak.
If the L wire is shorted to ground, the alternator would stop putting out if I read things right. At least on a series four (stock) it should. With a series five......I don't know for sure, because from the diagram the L isn't directly tied to the field as it is in a stock series four car. A series four L wire put to gnd should kill the alternator because you just killed the field voltage. No field voltage...no output.
Why my series four with series five alt works right off the bat with no L wire input is something I expect to figure out in the next day or so.
By the way, in the last part of that article attached, it talks about Self Excitation. Now I have seen that on a series four alternator with the plug off. No output when initially started, but if the engine is rev'd to say two grand and up, you see the volt meter jump up as the alternator gets excited and from there on remains excited til you turn the car off. I'm thinking the series five and six alternators are not like that. I hope to find out in the near future. I've a hunch the ariticle attached is referring to alternators like the stock series four and not the series five/six.
That said, I have a series five alterntor in one of my cars outside. The Warning light stopped working because of the usual cold solder joints on the warning light assy (I proved this by pulling the plug off the CPU and grounding the Y/L wire going to the Warning Light assy and they didn't all light up as they should when that is done).
So, I can start that car up and looking at the RTEK/Palm, I see 13.8vdc on the Palm right away. There is no L teminal wire connected in essence because the plug is off the CPU. If I take a digital meter to the alternator the ouput voltage is in the 14.3 range, so the real output is 14.3 not the 13.8 on the Palm. A voltage drop due to the ECU doing *stuff* or working so to speak.
If the L wire is shorted to ground, the alternator would stop putting out if I read things right. At least on a series four (stock) it should. With a series five......I don't know for sure, because from the diagram the L isn't directly tied to the field as it is in a stock series four car. A series four L wire put to gnd should kill the alternator because you just killed the field voltage. No field voltage...no output.
Why my series four with series five alt works right off the bat with no L wire input is something I expect to figure out in the next day or so.
By the way, in the last part of that article attached, it talks about Self Excitation. Now I have seen that on a series four alternator with the plug off. No output when initially started, but if the engine is rev'd to say two grand and up, you see the volt meter jump up as the alternator gets excited and from there on remains excited til you turn the car off. I'm thinking the series five and six alternators are not like that. I hope to find out in the near future. I've a hunch the ariticle attached is referring to alternators like the stock series four and not the series five/six.
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