307 alternator

[DeeTurbo]

Hi,

The alternator on the 307 HDI has a two pin plug on the top where the one on the 306 HDI has a single screw connection that goes to the battery light. 

Does anyone know what the second pin does on the 307 alternator?

[pug306driver]

sorry cant help with that one but see wiring diagram which may help....they are on here ??

[DeeTurbo]

I've tried looking for a wiring diagram online but haven't found anything yet.

[Magenta Sunset]

is one pim big n the other little?

[DeeTurbo]

I think they're both small.

[DeeTurbo]

Found out last night what the pins are, one should have an L on it and it goes to the battery light. The second goes to the ECU.

Now anyone know what the wire to the ECU does?

[cully]

ecu possibly controls the regulator which changes the charge rate for the battery under different engine loads/speeds

http://www.autoelectro.co.uk/how-it-works-alternators

[Magenta Sunset]

according to my Haynes, 1 wire goes to the instrument panel, the other to the battery +ve via the starter motor terminal

[cully]

i will have a look at the pug drawings when im home

[DeeTurbo]

The only reason I've been asking about the 307 unit is because I was thinking of fitting one to my 306. The only reason being the 307 one has the overrun pulley.

A smart charge system would be nice if it was a separate module that could be installed but it seems it's built in to the ECU. I guess the system would need to know things like engine load for it to work better not just battery state.

I think I might look into using the 307 unit and put the 306 regulator on it if it fits or look at getting the overrun pulley on the 306 unit.

[Ruan]

Was thinking about this today.

Try a late 206 HDi alternator, they seem to have an clutched pulley also, as do C8/807s with the 2.0 16v and 2.2 16v engines, although whether the mounting bracket is the same I'm not sure.