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Does anyone know how to permanently disable the traction control?

My issue is that I am running smaller diameter rear tires (23.5") for autocross. Just holding the button will turn the traction control off initially, but whenever the car gets loose or hits a bumpy spot, it will come on and then it cuts power bad becuase of the smaller diameter tires.

So far the only way to get the car to run on these tires is to disconnect all 4 wheel speed sensors, which of course disables ABS. I have found without ABS I get lots of wheel lock and flat spotted some new Hoosiers today.

I have heard that the ECU looks to see if the switch is wired up, and if not it permanently disables it after 5 ignition cycles. Although, I tried this and it did not disable it.
 

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I cannot answer your question, but something isn't right.

Once you turn off the TC, how is it sensing anything and deciding to turn back on? That doesn't make any logical sense with regard to how it should operate. I suspect it isn't really turning off correctly?

xtn
 

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I have the pin put instructions from Lotus somewhere around here.... but if I recall correctly, the ECU looks for the two pins being connected (pressing the switch disconnects them). If the ECU does not see the two pins connected for some period of time, it permanently removes the TC option. All based on stuff I was told from Lotus 3 years ago... so YMMV and probably will.

If it was me, I would disconnect the wires from the TC switch.

That does not address the problem if your TC is actually working when it is supposed to be off, but it would be a start.
 

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I had switch removed for 3 weeks and had more then 5 starts (I would say a good 30-40 starts) and then plugged switch back in and it still worked. I have heard of the 5 start rule also, but it didnt work on my car.
 

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I had switch removed for 3 weeks and had more then 5 starts (I would say a good 30-40 starts) and then plugged switch back in and it still worked. I have heard of the 5 start rule also, but it didnt work on my car.
Well there you go then. I never could tell because we reflashed my ECU and then there was not TC after that.
 

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cory1000,

But did it stay off for the three weeks that the switch was unplugged? If so, that should satisfy trompazo's requirements.

xtn
 

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Randy, you can't disable the TC on the 05, its always on by default so the switch trick doesn't work.

On the 06 it detects the light in the switch, not the switch itself (since its momentary on theres nothing to detect), so the TC harness has to be disconnected

I wonder if the wiring itself is causing it not to detect properly, but it does disable it when it works properly :)

You have to hold it to turn it off, but turning it on only requires a few miliseconds, thats why its so easy to knock it.
 

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I wonder then if switch bounce when autocrossing is causing it to trigger. That would make sense.
 

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Thats what i'm thinking too, it doesn't seem like it ought to but i know some people swear they never depress it (apparently including peeps at lotus, but it was shown they were just tapping it lightly with the knee).
 

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I know on our PDR, that the switch is probably more robust (bounce resistant) than the one used for TC, and we had to add debounce code to our recorder.
 

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It protects agaisnt debounce for turning it off just not on, since it uses a timed interval for the off part.

maybe just a higher amperage switch instead, if thats what it is.

data logger on the switch + autocrosser = find out whats really going on.
 

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It protects agaisnt debounce for turning it off just not on, since it uses a timed interval for the off part.

Also makes sense since it would be a fail safe way of looking at it.
 

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OK found out why it doesn't appear to work, its the first 5 starts for a new ECU, not any 5 starts, my bench ecu's are always within the first 5 thats why I hadn't noticed earlier.

Update your local rep/dealer then we can fix the rumour :)

Maybe we'll be able to fix that remove the battery for 5 minutes to clear/reset the learn rumour next.
 

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I wonder then if switch bounce when autocrossing is causing it to trigger. That would make sense.
I have the same problem when tracking. Turn it off when I head out for the session, look down, usually before I've completed a lap and the dash light is off (TC on). I thought maybe my knee was hitting the button but maybe its from the tires hitting the curbs. Antone else have this issue on track?
 

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Lots of people say it happens to them on the track, but i don't think anyones proved conclusively that they're not accidently hitting the switch.

Though i do recall someone mentioning a relocation of the switch itself.
 

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Another possibilty is that the driver's leg is bumping the switch button and turning it back on. I wonder if a "protector ring" around the button would prevent this - something like an inverted pop bottle cap such that you have to stick your finger into the recess to access the button. You could even test this theory by turning off the TC, and duct taping a bottle cap over the button. Then test to see if the TC gets turned back on. If it doesn't, then you have figured out that bumping it is causing it to tun on.
 

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Or something like this?
Oddly enough there are 4 wires to the Traction Control switch; one is the momentary one, the other two - I do not know. At least one is for the LED.
 

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TC is only an option on these cars right? I would never buy one of these cars with TC as long as I had the option not to.
 

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two wires for the switch, one ground, one input to the ecu
two wires for the led one for ignition switched power, one output from the ecu.
 
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