alternator wiring help

[cooperquattro]

been out today and the charge light has packed up,alternator is not charging,i confirm this with the battery meter......bulb is ok .....when i groung the blue wire on the rear of the alternator the light still doesnt glow.....
is there a relay?????

[johne]

There is no relay.

The way many alternators work you need the warning light blub and circuit to work to turn the alternator on when the engine first starts.

John

[cooperquattro]

ye understand that ,but why no light when earthed??going to check continuaty on blue alternator wire to dash....then, i have no idea...........if i groud the alternor post i get a charge

[johne]

If the bulb isn't blown then as you say you need to check continuity of the blue wire back to the dash and through the bulb and check that there's +12volts on the other side of the bulb with the ignition on.

John

[cooperquattro]

ok,so had continuity through the blue wire all way to bulb(all good),had a live+12v to the other side(all good) NO LIGHT(not good),noticed a small voltage down the blue wire approx 1volt,not good
found the wire junction under the dash,why does the blue wire branch off into 3 seperate blue wires???
1 goes to rear of ignition....
so i cut the wire to the clocks and voltage has gone,abviosly something in the clocks is making this wire live,but what????

will it do any harm if i just simply wire a bulb to the alternator so it works???

[cooperquattro]

This system.according to what I have found out,doesn't need a light for the alternator to charge,it must use the volt meter as back up!!!
Anyhow,no light on dash but have 14 volts,and car now runs when you disconnect battery so will do for now