1124 cc Visa alternator wiring

[paul in normandy]

I've got a problem with a Visa Ducellier alternator.
The engine was taken out some time ago, and for some reason I didn't mark where all the wires went.
On replacement I cannot get the alternator light to go out. The alternator has been tested (twice) by a very reputable auto electrical enterprise and is apparently in good working order.
The problem is with the small spade connectors on the back, there are 2, one marked D+ the other L, and I'm not sure which the single wire should go to.
I've got 2 manuals, Haynes was not very helpful (there's a surprise) but neither was the RTA (French) one.
Can any one enlighten me?
Any help gratefully received.

[CitroJim]

Logic would suggest the L terminal (for light) as the D+ terminal is most likely in parallel with the big terminal that goes direct to the battery.

You can also ask your auto-electrician exactly how he tested the alternator and that may give you a clue as it's often necessary to apply 12V to the warning light terminal to initially excite the alternator into charging... This initial excitation voltage is provided by a path to +12V battery positive via the warning light and ignition switch when installed in the car...

Check for yourself by seeing if the alternator is charging by measuring the voltage across the battery with the engine at fast idle. It should be around 14v. If it is then measure the voltage on the D+ and L terminals in turn. If one is substantially less than 12V then that's the one to connect the warning light to.

If no charge is shown, stop and connect the warning light to the L terminal and then restart and see if it's now charging. Doing this will provide the alternator with an initial excitation voltage.

Connecting the warning light wire to either terminal will cause no damage so it's safe to experiment...

[paul in normandy]

Thanks for that Citrojim, I'll have another go tomorrow. Glad to hear that there won't be a bang if I get it the wrong way round!!