My old lucus alternator died for the third time last week so I went to our local auction website and picked up a Mitshibishi Charade alternator for next to nothing.

Alter the mounts a little hook her up and the battery voltage jumps up over 15 after giving it a rev. So it appears to be working. Issue is the warning light does not go out. It is the same light I used on the Lucus unit. I have wired S to the ignition 12 volt and L to the wire to the warning light. There are only the 2 terminals so I guess I can't have got this wrong.


I am guessing I have bought a dud or is there another possible explanation?

Your help is much appreciated.

Blair

The Charade over here has the denso alternator and needs a bit more wiring.

Loads of info inc wiring diagrams on the westfield world owners website.

Here you go

With out knowing what alternator you have I could be well wrong. Modern cars have the alt' ecu driven and the ecu puts the light out.

[Edited on 28/3/10 by big_wasa]

Thanks,

Not a denso worse luck. Bit bigger than I wanted but only cost me $5NZ so next to nothing. Thought I would keep my eye out for a light compact unit after I got mobile again.

As the light comes on the L terminal must be at 0V I guess.

Does anyone know what the terminal S is likely to represent. I assumed Ignition and that L was the lamp, but I wonder if I got it around the wrong way.

Thanks Blair

Not sure about the different alternator, but the normal way the 'old school' types work is this:

There is +12v on the one side of the warning lamp, so at rest, there is zero on the alternator side, and +12v on the other side so it lights. Once the alternator starts whacking out a voltage it means there is not enough of a voltage difference across the lamp so it goes out.

Sorry if I'm preaching to the converted

BTW, also a good way of putting a warning light in fused circuits, just pop (no pun intended) it across the fuse, if the fuse blows, the light lights

pm me an email adddy, i may have a book that will help

doesn't the charade need a 12v supply for the exciter circuit to kick the diodes in

tony

If your indicator light needs an earth to come on you'll need an NPN transistor fitted to give you this on most Jap alternators.
Fit the transistor a BC548-B will do with the collector to the pin on the alternator (pin 1 on most), the emitter to earth and the collector to the signal wire from your lamp.
You'll also need a switched live to the other connection on the Alternator for the exciter diodes (normally pin 2).
The diagram on the Westfield site wont work for normal applications though it is useful for pinouts.
HTH.
Cheers,
Bob

Thanks Bob,

I think I understand what you mean and will give it a go.

Cheers Blair

You'll get the tranny from any electronic store Blair (Maplins in the UK) dont know about New Zealand. The pinouts for it can be found on the web, if your stuck u2u me. Basically your using the output of the alternator to use the tranny as a switch.
Cheers,
Bob