Wiring a shift light in

[koksracing]

Hi all,

I have a 182 ktec car and want a shift light on the dash.

I was going to buy the one in the link below, but could someone give me pointers on where I can wire it into to pick up the feed please?

Stack Panel Mount Shift Light

An ultra bright shift light mounted with a threaded body and lock nuts for securing to a panel. Supplied with wiring to connect to a Stack tachometer or other source. Available with red, white or amber light.

www.demon-tweeks.com

Thanks

Pete

 

[Touring_Rob]

Do you have a stack RPM gauge?

Also - absolute piss take given its a 50p LED.

 

[Brigsy]

Itll need to work on the canbus if using oem ecu.

Assuming gen 90 if ktec control car you may have an rpm feed that will work.

 

[Touring_Rob]

Itll need to work on the canbus if using oem ecu.

Assuming gen 90 if ktec control car you may have an rpm feed that will work.

Brigsy I think this is literally just an LED with nothing else smart, supposed to plug into an output on a stack gauge. If he has a gen90 I assume that could have a programmable output to drive any old light.

 

[Ol’ Tarby]

Brigsy I think this is literally just an LED with nothing else smart, supposed to plug into an output on a stack gauge. If he has a gen90 I assume that could have a programmable output to drive any old light.

If it's literally just an LED, which it looks like it is, then that price is absolutely f**king shocking!

Send it back and buy any bulkhead mounted LED off eBay for about 2 quid

 

[Touring_Rob]

Pretty certain it is:

T0063AOFAA | Indicator Bulb Holder, , 12.7mm Panel Mount | RS

uk.rs-online.com

 

[MarkCup]

Are you lot blind? That Tweeks one has actual wires with a thumbnail sized piece of heatshrink around them.

Well worth it.

 

[koksracing]

Yeah it is a rip off - 100% right

Pretty sure that the gen 90 ecu is that locked down it won’t give me even an rpm output but will ask ktec

Thanks

 

[Ol’ Tarby]

Yeah it is a rip off - 100% right

Pretty sure that the gen 90 ecu is that locked down it won’t give me even an rpm output but will ask ktec

Thanks

Does it not give a switched 12v or a switched ground at a certain RPM that can be set on the ECU?

 

[Touring_Rob]

As @Ol’ Tarby above says. All you need is a single switched output from the ecu. Super easy to do, an output just goes low at your set RPM. Then its 12V - Resistor - LED - ECU pin.

 

[Ol’ Tarby]

As @Ol’ Tarby above says. All you need is a single switched output from the ecu. Super easy to do, an output just goes low at your set RPM. Then its 12V - Resistor - LED - ECU pin.

How do you work out what resistor you need? I can't remember!

 

[Touring_Rob]

Depends what LED you choose,

Say you use this one which has a 2V forward voltage, max 30mA:

Kingbright2 V Red LED 5mm Through Hole, L-7113EC | RS

uk.rs-online.com

Easiest to use one of the many online calcs:

LED Series Resistor Calculator | DigiKey Electronics

DigiKey's LED series resistor calculator uses supply voltage, forward voltage, and forward current values to help you identify the correct series resistor.

www.digikey.co.uk

Gives a resistor value of 400ohms. But its a bright LED, better option is to run it at half current and see how bright it is so an 800 ohm resistor, an even fancier way would be to run a 400ohm resistor with a 1k adjustable resistor in series so you could change the brightness to suit.

With 15mA and forward voltage of 2V the calculator states that you need an 800ohm resistor and that resistor will dissipate 0.18watts - so a standard 1/4 watt axial resistor will be just fine.



OP - Holder for LED:

468 for '5mm LED holder ' | RS

uk.rs-online.com

 

[Brigsy]

Brigsy I think this is literally just an LED with nothing else smart, supposed to plug into an output on a stack gauge. If he has a gen90 I assume that could have a programmable output to drive any old light.

Indeed it would fit my stack dash. I was going to fit one but spent an horrendous amount of money on the sequential one instead, brighter than the sun in daytime mode