Alternator Wiring, Bosch

[sclarke7171]

Hi,
I have a Disco that the Alternator packed it in so i grabbed a new one i had in the shed for my Volvo and bolted it in.

OK here is the tricky part. It has a regulator built in. No problems and a plug that connects to it with 2 wires marked as "L" and "S" Ok easy "l" Light/lamp, "S" Signal for a Battery reference voltage.

The "S" one i'm interested in knowing more.
Is it a constant 12V from the Battery or switched via the ignition?

I've got it wired thru the ignition and now that the battery is charged when i use the indicators or anything with load the Charge lamp comes on.

OK if i hit the brakes it does not light until i release the brake pedal. It is like it is trying to tell me it is has fully charged the battery and the load from the brake light makes it charge again and when i release the brake it stops charging as the battery is full. Hence the light coming on for a second as the reg says "stop charging" and the voltage of the battery is highter than the Alt voltage?

Any ideas?

[Woop]

The 'S' connection is the Battery voltage sensing terminal for the regulator in the Alternator. This can either be connected to the battery or connected in parallel with the Alternator main output that goes to the battery. The 'L' terminal is the ign feed to energise the Alternator--this is normally wired via the IGN warning lamp, hence the 'L' designation. In newer Bosch Alternators,, these connections are made to the regulator via a small 2 pin connector .. Bosch Alternators are pretty reliable--make sure the case is earthed properly--if its wired up as above it should work ok..

Nick

[sclarke7171]

I'll try moving the "S" to the output of the Alt. or battery.
It could be a volatge drop thru the ignition the way i have it wired causing all the problems.
It is British leyland so we have to expect problems

Regards
Steve