Launch Control not working correctly

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WUZ
Posts: 23
Joined: Fri Aug 08, 2008 12:48 pm

Launch Control not working correctly

Post by WUZ »

During the mapping session with my mapper a months or so ago we mapped the car but with Launch control function ON, every time we go to 5000rpm whilst driving the car would splutter and hit an imaginary limiter ie, activating Launch Control whilst we were on the road in any gear at 5000rpm.

First thoughts would be the Speed sensor but the Speedo is working fine and from what I have been told, the signal for the speedo on our 2004 JDM STi comes from the ECU so why will the Launch control activate whilst on the move.

I need this sorted to be 100% happy with the car and the ECU - why spend the money I have spent on the Syvecs (S6 PNP, by the way) and not have all the functions work. Apart from the L/C, the car runs perfect on all the maps through the CAL switch.

Please help, I just need direction to help sort this out.

Russell

ps - I trust the Mapper implicitly, I have no issues using him again as I do not thing he has made a mistake in the mapping - but neither of us can figure out what the issue is
TimH
JT Innovations
Posts: 718
Joined: Wed Sep 01, 2010 3:51 pm

Re: Launch Control not working correctly

Post by TimH »

Maybe set "maximum vehicle speed for activation" to something low? And make sure exit speed and re-enable speeds are set right? 24kph, 16kph and 6.4kph in my CAL and that works fine without need of a launch enable switch.

Help info in SCal is pretty detailed for launch control, so maybe read that and see if your CAL makes sense?
pavlo
Zen Performance
Posts: 407
Joined: Mon Aug 04, 2008 10:18 am

Re: Launch Control not working correctly

Post by pavlo »

Sounds like the speedo is not working fine.

The speedo sensor in the gearbox creates the signal and it's read by both the ECU and instrument cluster. If the car has a poor speedo fix that may be your problem, or just that the ECU is not properly configured for the speedo sensor.

In terms of the LC settings, you need to ensure the Launch Control->Maximum Vehicle Speed For Activation is low, default is 6.2mph or 10kmm, and also that Launch Control->Exit Vehicle Speed is relatively low, as this sets the end of launch or started the exit timer.

The first thing you should do is ensure Vehiclespeed is logged and check a datalog, or check it with a gauge in Scal or SMon and observe that it goes above the required limits as set out in the launch control

You should also look at "Limpmode" as your 5000rpm may be a warmup limp limit for the oil temp or coolant temp. ALso be aware that if they are not up to termperature soon enough they will default the respective sensor and leave you limp mode until you power off/on or program the ECU.
pavlo
Zen Performance
Posts: 407
Joined: Mon Aug 04, 2008 10:18 am

Re: Launch Control not working correctly

Post by pavlo »

Also worth checking to see if the speed sensor is configured to ultimately give Vehicle Speed, as that's what the LC uses. So the sensor is usually configured for Radar, and then Vehicle speed is usually set to be Radar in turn, meaning that the actual speed sensor in the box is giving you vehicle speed.

Also worth checking that the Radar sensor (assuming correctly defined) has the pullup set to 'ON' as it will be needed for the sensor to work.

CHeers

paul
WUZ
Posts: 23
Joined: Fri Aug 08, 2008 12:48 pm

Re: Launch Control not working correctly

Post by WUZ »

My mapper did mention something about him being able to see the speed reading on the Syvecs software on the Laptop but could not get the L/C to work as stated above.

How do we change the readout of the Speedo from Radar to Speed.

Would the SPEEDO CONVERTER currently wired into the car (it is a JDM) be an issue?

Thanks again for your input guys, much appreciated.

Russell
pavlo
Zen Performance
Posts: 407
Joined: Mon Aug 04, 2008 10:18 am

Re: Launch Control not working correctly

Post by pavlo »

It's important that the Vehiclespeed is working, and not just Drivenspeed or just Radar speed on it's own.

The simple answer is to add the relevant parameters to the log and get it checked. You want to see launchrpm, launchexittimer, launchstate, vehiclespeed etc.
WUZ
Posts: 23
Joined: Fri Aug 08, 2008 12:48 pm

Re: Launch Control not working correctly

Post by WUZ »

Perfect, once I get back into the UK on Sunday I will Datalog the aforementioned parameters and see what we can see.

Thanks Paul, lifesaver once again.

Russell
Jolly Green Monster
Posts: 25
Joined: Mon Jul 28, 2008 9:06 pm

Re: Launch Control not working correctly

Post by Jolly Green Monster »

If this is still an issue then we best rewire said sensor when I am next up WUZ
WUZ
Posts: 23
Joined: Fri Aug 08, 2008 12:48 pm

Re: Launch Control not working correctly

Post by WUZ »

Sounds like a plan Simon, I know that Marc was looking to get you up in the New Year and I think I will have 4 cars in total for you to work on, just need to get some dates confirmed.
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