Thread: Stop Solenoid Problem...

Originally Posted by rijidij

This sounds just like what mine does. Can you give us some more info on the diode, what is a diode compared to a resistor, where it goes, etc.

Cheers, Murray

sorry its an elecie thing, and something i actually have not bothered to do. though i did wire up a light bulb to the handbrake which did the trick. but that got the flick when i fitted a disco hand brake.

a light bulb is also a resister in practice. a diode is like a one way valve, like what is fitted to second battery chargers, so it can charge but not drain back.

flick YT110 an email he has done it, or just truck into an auto eleie place, any one with out pimples will know what you are talking about

it is placed in the alt, but that is not the only place it can go, i guess the trick is matching the diode.

in fact since this question comes up often. ill check it out on Monday and see about making a sticky.

be careful doing the diode thing, as diodes have a voltage drop across them, depending on the configuration of your alternator you can wind up lifting the charging voltage above whats good for your batteries.

if you have the OEM alternator its usually an internal diode thats failed allowing the back feed, fitting another diode in the line wont cause issues until you replace or repair the alternator.

almost any diode with a current carrying capability of more than an amp should do the job

as they're one way grab a test lamp and when you wire it into the ign wire or sense wire for the alternator you want to set it up so that a small test light will light when the igntion is turned on the light will light if you probe the alternator end of the diode.

Originally Posted by Blknight.aus

be careful doing the diode thing, as diodes have a voltage drop across them, depending on the configuration of your alternator you can wind up lifting the charging voltage above whats good for your batteries.

if you have the OEM alternator its usually an internal diode thats failed allowing the back feed, fitting another diode in the line wont cause issues until you replace or repair the alternator.

almost any diode with a current carrying capability of more than an amp should do the job

as they're one way grab a test lamp and when you wire it into the ign wire or sense wire for the alternator you want to set it up so that a small test light will light when the igntion is turned on the light will light if you probe the alternator end of the diode.

quite correct, that why i started my post with if you have changed or upgraded your alt from the piddly little 40AMP job that was original. i have only seen 1 4db ever with the original alt, and that had been parked up for 20 odd years
i need to ask about because in the back of my head i think there are two easy choices of upgrades and one has this problem Hitachi i think
but what you have posted is valid and good info

Blocking Diode QTY 5 3Amp Automotive 12 24 Volt Plug IN KIT Aircon LED | eBay


will do the trick i am told.

placement is apparently in-line with the ignition light on the dash, it is feed back through this i believe,

nb i have not done this myself yet

Or just switch the bulb to an LED.

Originally Posted by Dervish

Or just switch the bulb to an LED.

Wouldn't it blow the led?

You can get LED's that you can plugin 12v directly. (Built in resistors I assume).

Eg the ones Dervish posted about in another thread: 12V Mini Chrome Bezel - Green | LED Modules | Optoelectronics | Active Components | PRODUCTS | SL2645 | Jaycar Electronics

Edit: it says on the page, "Includes dropping resistor"

Thanks Judo, yes - I mean the 12V LED modules. This is the one to get if you have the standard warning light cluster, it's a direct replacement for the existing T5 bulb and bulb holder:

T5 B8.5D Replacement LED Globe (Red) | Lighting | Car Safety Products | Automotive & Mobile Security | PRODUCTS | ZD0385 | Jaycar Electronics

Just be careful when installing them, the contacts are quite fragile.