Charge / Ignition light always lit

[Swiss_Toni]

I was wondering if anyone has any insight on why the yellow warning light on the dash is always lit?

The alternator is clearly charging but the light remains on and stays lit once you turn power on and after you start the engine.

I’ve looked at the wiring diagram and it looks like the wire for this goes from the alternator, to the light to the ignition switch. What turns this light on and off?

I’ve installed a new alternator, however it was the same as the previous one as well.

Thanks for your help.

[Steve_D]

Swiss_Toni said:

I was wondering if anyone has any insight on why the yellow warning light on the dash is always lit?

The alternator is clearly charging but the light remains on and stays lit once you turn power on and after you start the engine.

I’ve looked at the wiring diagram and it looks like the wire for this goes from the alternator, to the light to the ignition switch. What turns this light on and off?

I’ve installed a new alternator, however it was the same as the previous one as well.

Thanks for your help.

First the 'How it works'.
The lamp is connected to both the ignition switch and the alternator. There are no other connections to the lamp. (you may need to check this in case you have mistakenly added an earth).
When you switch on the ignition current passes through the lamp and earths through the alternator. This also stimulates the alternator to start charging. When the engine is running the alternator now puts +12v down the wire to the lamp. As the lamp is now recieving +12v from both directions it cannot light. This is why when your charging circuit is not quite right the lamp glows a little because there is not quite the same voltage on either side of the lamp.

As I said above you may have inadvertantly earthed the lamp and perhaps wired both the switch wire and alternator wire to the same terminal on the lamp.

Steve

[dal2litrefrogeye]

err ?? ill stand corrected , but isnt the yellow light the oil light , it is on mine , its usually red for charge, orange/yellow for oil pressure ,

[Swiss_Toni]

Wahooo, not 1 problem fixed but 3!!!

Some numpty connected the charge light (yellow), Oil light (Red) and the Oil gauge all in the wrong places!

Thanks a bunch, I never would have guessed 12 VDC from both sides but makes sense when you think about it.