DI switch light

[fakethinkpad]

Can a DI input with pullup resistor ON be used to drive a 12v light (have a 5 pin switch with built in lightbulb)?

If so, i also hade a 5 pin momentary switch (for LC) that functions as intended but want to add a light to tell if its active, us this possible? cant figure out how to make it happen using only the DI and i dont see any outputs that might help on the XS loom either.

 

Thanks in advance,

Christian

[Adamw]

I think it would work if you do the opposite - that is turn off the pullup and have the switch supply 12V.

Excuse my MS paint skills:

Edited August 7, 2016 by Adamw
Image didnt show

[fakethinkpad]

I think it would work if you do the opposite - that is turn off the pullup and have the switch supply 12V.

Excuse my MS paint skills:

 

Thanks Adam, appreciate that very much, much simpler than expected. This solves the normal rocker switch but am i right that the momentary switch would require a Aux channel to control the lightbulb or is there any other way around that?

Could i use a Volt input from the +V switch and trigger DI with pullup to the light? or is the Volt input not able to handle 12v?  

Edited August 8, 2016 by fakethinkpad

[Adamw]

I'm not quite sure I understand what you are trying to do with a momentary switch, are you using the "latched launch" mode?

Could i use a Volt input from the +V switch and trigger DI with pullup to the light? or is the Volt input not able to handle 12v?  

Sorry, I'm also not clear what you are asking here.  Perhaps you can draw a quick diagram (even a photo of a paper drawing) and explain what you want to happen/how you want things to work.  A picture of your switch might help too since "5 pin" doesn't mean much.

[fakethinkpad]

Sorry if i wasent clear enough, ill try from scratch;

i have a momentary switch that i want to use for Launch Control (press once to activate, press again to de-activate) and i have the function working like your drawing above with the exception of the light. now, the problem being a momentary switch i dont know how to wire the light to go by the active state from the ECU, it would simply blink once when i press the button.

Thats why i think there is no way around the fact i need to be using a Aux as the ECU is the only thing that knows the state of the switch (or LC to be specific), lets say i activate LC and turn the car off that would change the LC state to Off when i start it up again. its either that or use a normal rocker switch or am i wrong here?

Hope it makes sence,

Christian

Edited August 9, 2016 by fakethinkpad

[Scott]

Hi Christian,

You will need to use an Aux Output to control the light unless you change to a rocker switch.

Scott.

[fakethinkpad]

Hi Christian,

You will need to use an Aux Output to control the light unless you change to a rocker switch.

Scott.

Thanks for confirming Scott - is there anything i can use on the board - unfortionatly my PnP ECU dont have Any Aux on the XS loom and if i understand the manual there are no Aux free to use for the R34 GT-R?

[Adamw]

i have a momentary switch that i want to use for Launch Control (press once to activate, press again to de-activate) and i have the function working like your drawing above with the exception of the light. now, the problem being a momentary switch i dont know how to wire the light to go by the active state from the ECU, it would simply blink once when i press the button.

Thanks, now I get it.  As Scott says, the easiest way would be an aux out or change to a toggle/latching button .  It would be possible to build an external latching circuit for the lamp but it seems a difficult way to achieve the need.

 

Edited August 9, 2016 by Adamw
typo.

[Scott]

Thanks for confirming Scott - is there anything i can use on the board - unfortionatly my PnP ECU dont have Any Aux on the XS loom and if i understand the manual there are no Aux free to use for the R34 GT-R?

The expansion connector on the V1.0 to 1.2 bottom board do not have any Aux Outputs on the expansion connector. However from V1.3 onwards there is a second expansion connector that has two Aux-Ign and an Aux Output available.  Which version do you have?

Are you still using the factory fuel pump speed control? If not you should have Aux 1 and Aux 2 available on the main ECU connector.

Scott

[fakethinkpad]

Main board revision is V1.2 im afraid, and i do run the factory fuel pump control (this takes up two Aux?) so i guess im out of options, old G4 does make you feel claustrofobic at times.

[Scott]

Sounds like a rocker switch might be the easiest way to go.

Scott

[fakethinkpad]

It seems that way; but thanks a lot for helping out with the diagrams Adam, that helped me getting the light to works, and Scott for support and clarification.