Three pin and Two pin Alternators

[teliocide]

Can a 2 pin alternator be installed in a vehicle as a replacement for a 3 pin alternator.
From my limited understanding the third wire on the plug is the control line for turning off the alternator when there is minimal electrical load, lights off, cabin blower off, etc to supposedly save fuel.
I imagine this control line turns off the power to the armature.
Words of wisdom please>

 

[rjenkinsgb]

There are a number of variations, you cannot be sure without comparing the wiring diagrams from the vehicles they are used in.

Connecting one just based on the number of connections could cause serious damage...

The most basic types only have one external connection, for the alternator warning light (not counting the main power terminal).

Just having two terminal give a number of different and incompatible variations.
Three multiplies that again..

 

[teliocide]

Thanks,
All that is stated is known. So I need to re-phrase the question.
The three connections are:
S = battery voltage sensor
L= Warning lamp
C= generally the connection the ECU
The two pin alternator has only the S and L connection and NO connection with the ECU.
It is reported that some three pin alternators have go a default state of internal regulation if the link to the ECU is broken.
There are also sold 3-pin to 2 pin conversion plugs which suggests 3 pin alternators will function happily with no C connection.
The question becomes...." will the ECU spit the dummy" if there is no C connection?

 

[rjenkinsgb]

The question becomes...." will the ECU spit the dummy" if there is no C connection?

That's down to the ECU programming, what conditions are needed to trigger a fault code.

The alternator itself should work fine, but it's possible the ECU may give a fault after some time, if it detects the battery voltage is not being controlled as it commands.

You may be able to work around that, by changing a parameter? eg. in newer Fords, you can adjust the target charge level (in the Body control module setting).
By default it's typically 80% on those.

Changing that to 100% may prevent the ECU seeing a discrepancy caused by the different alternator?