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Discussion Starter #1 (Edited)
I:pOOTON THE FIRST FOR THE CURE

Rasp: LOL:LOL:LOL:LOL:LOL:LOL:LOL:LOL:LOL:LOL:LOL: Rasp:


As promised the how to T: anyone can use this circuit but not for profit making!!:no


For all those of you who want Blue dials and cant get hold of ABL specific ones or have, and given up, because of the revcounter and charge light not working. READ ON

Other dials do work! there cheap on Ebay £30 ish delivered. Dont throw the ones you have away.
They must not be CanBus, the only reason im saying that is i havent played with them to prove they would or wouldn't work!
Also make sure there not encoded to the ECU. There the ones normally sold in a trio ECU transponder and Keys.

After much thinking and reading up on alternator theory heres the cure.

You will need 4 wires each 500mm to 1 mtr long, 1.5mm cable, 1x 10 amp relay MUST be fused type!,1 x 7.5 amp blade fuse, 3 x 10 watt 20 power resisters, 6 x pcb mount terminals. small project box with pcb bread board.

Heres the circuit:-




BEFORE making any connections disconnect battery earth check wether you need to turn alarm off!
ALWAYS make sure connections are tight! Soldered and heat shrunk!

your earth can be obtained from the donut ring under the dash.
12v Pos from red plugs at back of fuse board plate too the right.
splice into cable at back of relay fuse board (F/3) 0.5 blue.
splice into cable at back of relay board (F/1) 2.5 red/black wire.

What this little circuit does:-

The relay switches 3 x 20ohm (10 WATT CERAMIC A MUST) resisters across the D+ and 12V battery supply! using the ignition starter wire (the solenoid one) to power the relay.
whilst you turn the key the circuit works whilst cranking.

They do this in windmill generators exiting the rotor coil for low wind speeds totally harmless!!!!!!!!!
so rather the alternator self exiting its self at 2500 to 3000 RPM it now starts working at about 800 RPM.

Old cars used a fat bulb in charging circuit for this same effect. i would love to get my hands on ABL specific dials or the fuseboard as theres that little extra in there that's not being documented in wiring diagrams and schematics on the vehicle change.

This is what happens before and after:-

I:
 

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Nice little thing you have built there,

So I take it the later dash doesn't use a bulb for alternator load to get it to energise?, must be an LED and get's energised somewhere else as an LED won't work. I have those clocks in my Van but mine are CANBUS so might work differently, may have a look where the alternator wire goes though. See if it goes straight to the dash or to a relay/load somewhere else, if that's any help to you.

I'm surprised the alternator gave any output from just revving it to energise, some wont do that!.
 

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Discussion Starter #3 (Edited)
Nice little thing you have built there,

So I take it the later dash doesn't use a bulb for alternator load to get it to energise?, must be an LED and get's energised somewhere else as an LED won't work. I have those clocks in my Van but mine are CANBUS so might work differently, may have a look where the alternator wire goes though. See if it goes straight to the dash or to a relay/load somewhere else, if that's any help to you.

I'm surprised the alternator gave any output from just revving it to energise, some wont do that!.

You could do? be nice to know whats different especially if they have some sort of load relay tucked away?.

This is for people who want to convert old van style clocks to the blue plasma glow with red illuminated needles and have them working perfectly :D

Talking to many others who have done the conversion ( the rev counter, oil , charge light wont work) this is as far as youll get until you install this little circuit!

Unless your luckily enough to come across ABL fitted ones which must have a bulb in them like the old fashioned way!

I have a set of Bora clocks im going to experiment with now. paid £19 delivered will need some sort of pull up resister i think for the fuel gauge to work properly and again the above circuit to make the charging circuit work properly. T:
 

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Err....maybe I'm over-simplifying this, but have you tried simply putting a bulb between D+ and the ignition wire?

Ignition off...no current through bulb, ignition on, supply through bulb to the "earthy" D+....alternator rotates, D+ goes up to supply voltage, bulb goes out as no current flows.
No relay, you hot resistors...just a bulb either in the dash, under, or in the engine bay.
A couple of watts is normally all that's needed, but if you want it really bright, we used to fit 21 watt bulbs on the dash for "noisy" places where you didn't always hear that the engine had stalled! (Stock car racing).

That's all the "old" system used to supply startup current to the field windings.
 

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Yeah i'd be happy to have a look, though I need to find a diagram of where the wire goes after the firewall! :)
 
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