Do you need diode in the alternator wiring?

[Mattt]

Just had the alternator fitted (Land Rover Discovery one I believe), and the Auto Electrician didn't put a diode in the loom as he couldn't see why it needs it.

There are no lights etc on in the dash, do they definitely need this diode & why?

2006 T350 by the way.

[darkmark07]

The diode's there to stop a current back feed when the engine's not running - the fact that it's not installed shouldn't prevent the alternator from charging the battery in the first place.

When the diode packed up on mine, the dash pod was on even without the key in the ignition. This would kill the battery in < 5 days, even on an accumate.

My thread here: http://www.pistonheads.com/gassing/topic.asp?h=...

I think that LeeT350's post expains about the diode in more detail.

Good luck

Mark

[Mattt]

I have no diode and my dash seems fine (i.e. it's off).

I assume because I have a 'pukka' alternator not a cheaper one like mentioned, it must have this feature. The Auto Electrician said in my old alternator he couldn't see any special diode.

[Mattt]

Bump...

[darkmark07]

What further info do you need? You seem dismissive of the info given and seem to have decided that the diode is either in place or not necessary.

How can we assist you further?

[Mattt]

I'm not dismissive, the Auto Electrician is.

Is there anything that should be noticeable if the diode is required, e.g.LCD on or battery light on etc.