Thread: Alternator wiring Hitachi 4bd1t Defender

Ok, here's the plug you've got...



Take the "S" lead (sense) to the insulated terminal on the alternator then direct to battery.
Take the "L" lead (lamp) to the ignition light
Take the "I" lead (Ignition) to 12V switched from the ignition switch.
Connect a ground to the alternator.

Should look something like this...



Cheers
Pete

I am watching this thread for my own education

Don't be tempted to get your Voltage Sense "S" from the loom - get it direct from the battery and make sure the connects and wire is good otherwise you'll get voltage drops and the alt will over charge. This may not cause any issues right away but you'll burn out your lights faster, and everything will run hot (radio, anything) and wear out faster.

Originally Posted by flagg

Don't be tempted to get your Voltage Sense "S" from the loom - get it direct from the battery and make sure the connects and wire is good otherwise you'll get voltage drops and the alt will over charge. This may not cause any issues right away but you'll burn out your lights faster, and everything will run hot (radio, anything) and wear out faster.

This is the solution I came up with.
It charged about 12.5v on start up then switches up to 13.5v+ after the Defender glow plug relay tapers off. It starts and runs without that notorious 'cold 4BD1' shuddering and vibration- I think because the glow plug relay runs the plugs for some period after start up.
Pics attached.

I still haven't figured out the wiring for the EDIC shutoff solenoid. I've looked at all of the AULRO posts on the subject -bought a suitable relay- but have the same issue 'what lead goes where' from EDIC to relay. May post up here in a new thread to get some advice.

on start up cold 12.6v. Charge light on dash illuminated.
On revs, 14.4v and stays there irrespective of engine revs (idle or 2000k rpm). Charge light on dash goes out.
Reduces a bit to 14.3v when lights are on.
Too high? Seems a bit high to me. I would have expected to see more variation and a lower rate of charge on idle- climbing to this level (14v+) at revs.