Increase VN V6 S1 DFI Tacho Signal output ??

Holden/Delco Tuning. ALDL, OBD 1.5. Circa 1989 to 2004.
S1VNV6Hilux
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Re: Increase VN V6 S1 DFI Tacho Signal output ??

Post by S1VNV6Hilux »

Pin G on the dfi (BLUE/yellow) is the recommended input for the tacho interface (Divide by N) then the output from the the interface is connected to the (BROWN) tacho wire - this is the instruction from Marks 4wd.
All i know about the electrical difference is that on a series 1 the output on pin G is 5v output pulse (possibly less) and on the series 2 it is greater than 5v - in the instructions from Marks it mentions that series 1 may not have enough voltage to drive the interface. (mine doesn't) it's more like 3.5v.

Basically i was wondering is there was a simple circuit that could boost the voltage output as i already have a good working dfi/coil pack and the interface. - it is looking like the upgrade to a later dfi model and coil pack maybe the way to go so i can use my existing interface. i was thinking of using a VR one - would this be a straight out plug and play option ?

Having said that i am still very interested in finding a different solution.

Dieselbob - how would you go about connecting a tacho to pin H ? i was led to believe that most tachos including aftermarket ones need a voltage of above 5v to work ?? do you know the voltage output on pin H ? keeping in mind i still need the divide by N to allow the use of my 4cly hilux dash

thanx to everyone for your input and help so far - greatly appreciated :thumbup:
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DieselBob
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Re: Increase VN V6 S1 DFI Tacho Signal output ??

Post by DieselBob »

Pin H is the input from the 3 pulse hall effect both this and the 18x are fed by the same circuit, VL400 might have an idea about voltages. I assumed it would be the same as the voltage on pin G.
There might be a problem with the trigger edge (rising/falling) as the pulses are differant lengths to id cylinders.
I need to look at VL400's circuit so I'm not suggesting something already out there...........................
S1VNV6Hilux
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Re: Increase VN V6 S1 DFI Tacho Signal output ??

Post by S1VNV6Hilux »

Anyone no if the VR DFI & coil pack are a straight swap for the VN S1? is it possible to use VS-VY at all ??
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Holden202T
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Re: Increase VN V6 S1 DFI Tacho Signal output ??

Post by Holden202T »

yeah i believe they are all the same
S1VNV6Hilux
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Re: Increase VN V6 S1 DFI Tacho Signal output ??

Post by S1VNV6Hilux »

Cheers Holden202 - i was wondering because some are listed VN-VR and others VS-VY. im guessing if i go VR i will be safe....
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Holden202T
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Re: Increase VN V6 S1 DFI Tacho Signal output ??

Post by Holden202T »

the alloy base is different for vs onwards, but i know the vn-vr all have the same alloy base.
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VL400
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Re: Increase VN V6 S1 DFI Tacho Signal output ??

Post by VL400 »

From memory the later style is around 8v square wave. If your still wanting to boost the S1 signal use the diagram linked to earlier and instead of a relay coil replace it with a 1k resistor. 3 parts and you will have a battery voltage square wave for the tach interface.
S1VNV6Hilux
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Re: Increase VN V6 S1 DFI Tacho Signal output ??

Post by S1VNV6Hilux »

VL400 wrote:From memory the later style is around 8v square wave. If your still wanting to boost the S1 signal use the diagram linked to earlier and instead of a relay coil replace it with a 1k resistor. 3 parts and you will have a battery voltage square wave for the tach interface.
Another novice question.... using the previous diagram what pins on the 2N5551 go where ? Emitter, Base, Collector ? is 0 v an earth ? :hmm:
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Re: Increase VN V6 S1 DFI Tacho Signal output ??

Post by VK_3800 »

I used a VS one on my old VN S1, as above you just have to tweak the base so you can physically bolt it in, there are no issues with electrical compatibility.
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Re: Increase VN V6 S1 DFI Tacho Signal output ??

Post by OZ38 »

Old post I know, but I have a Marks tacho adapter that is not working. I know it supposed to be wired to the blue/yellow wire from the dfi (CAS signal). It doesn't seem to work at all. I wonder if there is a way to check it, or the inputs & outputs ?

Cheers