Sport mode as default - potential fix - Interested?

[elandri]

Hi all,

Having to press the sport button every time really annoys me so I got thinking about how it might be automated.  After a bit of rooting through the wiring diagrams I decided to have a go at building a simple timer to simulate the button press.

Timing is important. I tried starting the car with the button pushed and it didn't engage sport.  So, it needs to be off when the engine started, then on briefly, then off again.  

Pencil out I explored a few designs & options but settled on the 555 timer as I had some to hand and they are one of the few chips that can handle 15V.   My circuit employs two 555s (you can get a dual 555 chip - the 556 - but I didn't have any) with associated components and an opto-coupler output.  With the basic idea drawn I breadboarded the circuit, refined a few component values and wired it in to the Evora.

Seems to work a treat.

I took power from the "Key in" line to the head unit (which I had out anyway), Ground and the Sport Mode lines come from splices into the  "Driving Switch" cable just behind the fascia. Those three are the only connections required.  

So, key in, timer1 starts, you have  approx. 15 seconds to start the engine before timer 2 gives a a simulated 2 second push in the button. 

Sport is engaged. If you want it off just press the button as normal.   

So, from here I could either just make a "proper one" on Vero board for myself or, if a few like minded individuals want to share the cost, we could have PCBs made. it's not very expensive these days. I'd guess I could get ten done for c£150-ish. 

Anyone interested?

PS - I must stress that, while this works fine in my garage, it hasn't had extensive on the road testing so there may be bugs to iron out yet.   

[agentdr8]

Nicely done. I had considered a similar project, but never sat down to sketch one out, as I started noodling on advanced features, like remembering/restoring button state, so it got infinitely more complicated and it hit the back burner. 

 

[elandri]

KISS! ☺️

[grog]

sounds great, i'm interested, are you thinking the 556 on the 'proper' pcb?

it might also be good to have the leads with a male and female plug compatible to the small plug on the buttons PCB, this way it'll be plug and play, and probably a good place to pick up Vcc and Gnd, i assume they are already on that connector. 

like this, but couldn't find a photo of the other side switches.

[elandri]

I've left the choice of 2 x 555 or 1 x 556 to the guy who's designing the pcb.

Plugs and leads would be tidy but (probably) a pain to identify the correct housing / terminals and crimp tool.

Some of those tools cost £100s.

They'd also take ages to make. 

I did look at the diagram but it's not at all clear (well, not to me) that there's a usable Vcc. It's all either signal out from ECU looking for Gnd through the switches or LED drives.

[stevensr34]

Would this design of circuit work for the Elise too?

[grog]

13 hours ago, elandri said:

I've left the choice of 2 x 555 or 1 x 556 to the guy who's designing the pcb.

Plugs and leads would be tidy but (probably) a pain to identify the correct housing / terminals and crimp tool.

Some of those tools cost £100s.

They'd also take ages to make. 

I did look at the diagram but it's not at all clear (well, not to me) that there's a usable Vcc. It's all either signal out from ECU looking for Gnd through the switches or LED drives.

looking at the connector it looks like a straightforward one, it may be possible to but the leads pre-crimped then cut in half to get 2 plug to wire assemblies from 1 cable. 
I could figure that out, but don't fancy pulling the car apart just to check, 

for the Vcc i assume there is something there for the button backlight on the sidelight switch, this is always on.

 

can't see any reason it wouldn't work for the exige too?

[elandri]

See Agentdr8 post on A N Other forum re difficulty of identifying/sourcing the econnectors:

"Not for the Sport button PCB. IIRC, last time I tried to find it, they weren't easily sourced and may have been an NLA connector from AMP".

Good idea re the sideamp backlight as Vcc source. I'd missed this because Sheet D1A in the PDF of the wiring diagrams I have is missing an inch or so from the the top and r/h edges of the digram so I can't see the LED, identify which wire goes to it or which source it might come from. Frustrating! 

Does anyone have a complete version of that sheet so we can idenify the correct cable?

On the 400 diagram the source is the "Key in" line - which would be good - but the colours are different.

 

Edited August 4, 2023 by elandri

[elandri]

4 hours ago, stevensr34 said:

Would this design of circuit work for the Elise too?

If sport mode in the Elise (or anythign else) is invoked by presenting a brief ground condition to the ECU it should work.

You'd need to check wiring diagrams to see.